I am given a simple river system flowing down a slope where the speed of the flow downstream under the force of gravity builds up until resistive forces $R$ balance the component of gravitational force acting downstream $F$.  $$R=av$$ $$F=bh$$  The speed will eventually adjust to when $av=bh \implies v=\frac{b}{a}h$. We further assume that rain add water and we let seepage into the ground remove water. This will increase the depth of water at any point in the river at the rate $r(h, x, t)$ and the mass conservation law is given by  $$h_t +(hv)_x = r$$  Using Burger's equation and substituting for $v$, I get  $$u_t +uu_x =f$$  where $u=2\frac{b}{a}h$ and $f=2\frac{b}{a}r$. My question is how one arrives at the proposed $u$ and $f$ expressions.  If $R=av^2$ instead and following the same procedure I arrived at  $$h_t +(\sqrt{\frac{b}{a}}hh)_x = r$$  Can I reduce this to,  $$u_t +uu_x =f$$  where $u=\frac{3}{2}\sqrt{\frac{b}{a}}h\;\text{and}\;f=\frac{3}{2}\sqrt{\frac{b}{a}}r \;?$


Kindly help me. i have created a run time spell check system. The problem i am facing is, when the system returns the correct spelling, it shows the word hyper linked. If the user clicks that hyper link, it should overwrite the word with the suggested work. Unfortunately the jQuery created hyper link is not triggering  i have created this dummy project, because actual code is very lengthy. JSfiddle link is this:       Testing


I am confused about what exactly a complete sentence. I have read that "Yes." can be a complete sentence, but the subject and verb in a "Yes." sentence are implied. I don't think that someone is expressing what they want to say by implying words. I know that someone can assume that someone else is trying to say "Yes, I like something.", but that doesn't mean that the person saying "Yes." is actually expressing what they are trying to say. Again, I would just like some clarification on what exactly a complete sentence(something that expresses a complete thought) is.


Estimate for $\sum_{q=1}^{M}\frac{\varphi(q)}{q^{2}}$ Related to Bourgain Paper

Let $N\gg 1$ be a large parameter, which I ultimately want to let tend to infinity. I am reading an old  of Bourgain, where he claims the lower bound (Equation 2.50, pg. 118)  $$\sum_{q=1}^{N^{1/2}-1}\sum_{{1\leq a < q}\atop{(a,q)=1}}\frac{N^{3}}{q^{2}}\geq c(\log N)N^{3}, \tag{1}$$  where $(a,q)$ denotes the GCD of $a$ and $q$ and $c>0$ is some absolute constant, the value of which I don't care and may change from line to line.  Using the following  for Euler's totient function $\varphi(n)$  $$\varphi(n)>\frac{n}{e^{\gamma}\log\log n + \frac{3}{\log\log n}} \tag{2}$$  and the PNT, I only know how to show that  \begin{align*} \sum_{q=1}^{N^{1/2}-1}\sum_{{1\leq a < q}\atop{(a,q)=1}}\frac{N^{3}}{q^{2}}&\geq c\sum_{{1\leq q<N^{1/2}-1}\atop{q=\mathrm{prime}}}\frac{N^{3}}{q^{2}}\cdot q\\ &+c\sum_{{1\ll q<N^{1/2}-1}\atop{q\neq\mathrm{prime}}}\frac{N^{3}}{q^{2}}\cdot\frac{q}{e^{\gamma}\log\log q+\frac{3}{\log\log q}}\\ &\geq cN^{3}\log\log N \tag{3} \end{align*}  If I knew the asymptotics of the series $\sum_{q=1}^{N^{1/2}-1}\frac{\varphi(q)}{q^{2}}$ or $\sum_{q=1}^{N^{1/2}-1}\frac{1}{\sigma(q)}$, where $\sigma$ is the divisor sum function, then my problem would be solved. However, I have been unable to find such information.    John M. has very kindly provided me with the necessary asymptotics. To see how to get that formula, first recall that $\varphi(n)=\sum_{d\mid n}\mu(d)\frac{n}{d}$, where $\mu$ is the Mobius function, and $\sum_{n=1}^{\infty}\frac{\mu(n)}{n^{2}}=\frac{6}{\pi^{2}}$. Then  $$\sum_{n\leq x}\frac{\varphi(n)}{n^{2}}=\sum_{n\leq x}\frac{1}{n^{2}}\sum_{d\mid n}\mu(d)\frac{n}{d}=\sum_{{q,d}\atop{qd\leq x}}\frac{\mu(d)}{d^{2}q}=\sum_{d\leq x}\frac{\mu(d)}{d^{2}}\sum_{q\leq\frac{x}{d}}\frac{1}{q} \tag{4}$$  Using the formula $$\sum_{q\leq k}\frac{1}{k}=\log(k)+\gamma+\epsilon_{k},$$ where $\epsilon_{k}\sim\frac{1}{k}$, and $|\log(y)-\log([y])|=O(1/y)$, we see that  \begin{align*} \mathrm{(4)}&=\sum_{d\leq x}\frac{\mu(d)}{d^{2}}[\log(x)-\log(d)+\gamma+O(\frac{1}{x/d})]\\ &=(\log(x)+\gamma)(\frac{6}{\pi^{2}}-\sum_{d>x}\frac{1}{d^{2}})-\sum_{d=1}^{\infty}\frac{\mu(d)\log(d)}{d^{2}}+\sum_{d>x}\frac{\mu(d)\log(d)}{d^{2}}+O(\frac{\log x}{x})\\ &=\frac{6}{\pi^{2}}(\log(x)+\gamma)-A+O(\frac{\log x}{x}) \end{align*}


Proof of identity $\sum_{k=1}^nk\binom nk=n2^{n-1}$

$$\sum_{k=1}^nk\binom nk$$ I have to write this as $n2^{n-1}$, and nothing I tried has worked so far. How should I approach this? Thank you


I have two questions on ext4:   Is there currently a way to mount an ext4 partition in Windows (XP/Vista/7) to get basic read support? If not, are there any plans to support this someday?


Ring switcher is not automatically selecting the windows on key release

I configured the ring switcher with the CCSM.  I press Super + Tab and I start to cycle between all windows, but when I release the keys on the desired one, I have to either click on it or press enter.  How can I make it automatically select the window when I release the key?  It was working, but suddenly it stopped doing it.  I have the same trouble with Shift-Switcher compiz plugin.


I'm trying to check if an enum option is contained in the available options. Its a little bit difficult for me to explain it in english. Here's the code:  public enum Fruits {     Apple,     Orange,     Grape,     Ananas,     Banana }   var available = Fruits.Apple | Fruits.Orange | Fruits.Banana; var me = Fruits.Orange;   I'm trying to check if the me varliable is contained in the available variable. I know it can be done because it's used with the RegexOptions too.


Use of an indefinite article associated with a particular person's name

Indefinite (and definite) articles are sometimes associated with a person's name.  is the best summary of the uses I have found.  Also,  addresses the issue that was not mentioned in the summary with the example sentence "when a defeated Napoleon rode off the battlefield and into exile", and it is followed by a couple of useful answers.  My question is related to the latter.  Let me add three more examples to clarify the point.   "muttered a startled [Michael] Fallon" (Author  or ) "an elated Sarah Storey after her victory" () "one photo showing an unsmiling Francis standing next to a beaming Trump" (   In any of these cases, as well as the Napoleon-related example, the person(s) referred to is precisely specified in the text and only one in the world.  I have heard of a hypothesis (from a friend) people sometimes use an indefinite article before a particular person's name when it is accompanied with a preceding modifier, which tends to be (though not necessarily limited?) the present or past participle form of a verb; in other words, the modifier is sandwitched between the article and person's name.  All the cases listed above fit the hypothesis and the modifiers are "startled", "elated", and "unsmiling" and "beaming".  If this hypothesis is correct, there is no expression like "a John Smith delighted with blah-blah" (as long as the referred John Smith is already narrowed down to a particular person in the given context).   to the aforementioned question explains     It's a literary/oratorial device. You certainly wouldn't often come acrosss it in normal speech - only somewhat flamboyant prose or speechifying.      Think of it as meaning that Napoleon is a man of many aspects, victorious on other occasions, but defeated this time. Using the article implies that this is only one of several possible Napoleons that have or will exist.   The first part fits my little Googling research; it seems this use of the indefinite article is more commonly seen in novels and fictions than other types of writings.  Applying the second part to my examples, the three example sentences are interpreted as "Fallon/Storey/Francis/Trump is a person of many aspects, but in this case s/he is only one (=startled/elated/etc) of several possible Fallon/Storey/etc", which seems fitting.  Now I am asking for further clarifications:   What is the condition where this use of an indefinite article is accepted?  Is the above-mentioned hypothesis (i.e., always(?) having a modifier in between) correct?  Are standard adjectives like "happy", as opposed to verbs in conjugation, accepted for it? What is the nuance of the expression?  Specifically, what is the difference from the phrase without an indefinite article? For example, how about "'blah-blah', muttered startled Fallon"? I think the definite article "the" would feel a little unnatural in this case, as explained in detail in .


In my course on linear PDEs, the professor used $H^{1/2}$ without defining it, and I have been looking on google trying to find a definition, but the only related thing I found was $H^{-1/2}$ as being the dual space to $H^{1/2}$ which does not really help. Plugging in the one half in the defintion of the standard Sobolev spaces $H^m$ does not make any sense. Could someone quickly help me out there? Thank you.


What is $\cos\frac{\pi}{13}+\cos\frac{3\pi}{13}+\cos\frac{5\pi}{13}+\cos\frac{7\pi}{13}+\cos\frac{9\pi}{13}+\cos\frac{11\pi}{13}$  I feel like this question shouldn't be too difficult but I'm getting stuck on it for some reason. I paired the first and last terms, second and second-to-last terms, etc, and used the sum of cosines formula to get   $\cos\frac{\pi}{13}+\cos\frac{3\pi}{13}+\cos\frac{5\pi}{13}+\cos\frac{7\pi}{13}+\cos\frac{9\pi}{13}+\cos\frac{11\pi}{13}=2\cos\frac{6\pi}{13}(\cos\frac{5\pi}{13}+\cos\frac{3\pi}{13}+\cos\frac{\pi}{13})$  But I don't know where to go from here.


How important is it to keep meshes low-poly? When I model I feel bad about adding high-poly detail and don't do it because when I started with Blender I read some stuff against high-poly modeling, but now I'm confused.


Do there Exist Proper Classes that aren't "Too Big"

Some proper classes are "too big" to be a set in the sense that they have a subclass that can be put in bijection with $\alpha$ for every cardinal $\alpha$. It is implied in  post that every proper class is "too big" to be a set in this sense, however I have been unable to prove it. It's true if every two proper classes are in bijection, but it's consistent with ZFC for there to be a pair of non-bijective classes.  So, is the following true in ZFC:     For all proper classes, $C$, and $\alpha\in\mathbf{Card}$, $\exists S\subset C$ such that $|S|=\alpha$?   If not, is there something reasonable similar that preserves the intuition about classes that are "too big to be sets"?


Prove: symmetric positive definite matrix

I'm studying for my exam of linear algebra.. I want to prove the following corollary:     If $A$ is a symmetric positive definite matrix then each entry $a_{ii}> 0$, ie all the elements of the diagonal of the matrix are positive.   My teacher gave a suggestion to consider the unit vector "$e_i$", but I see that is using it.   $a_{ii} >0$ for each $i = 1, 2, \ldots, n$. For any $i$, define $x = (x_j)$ by $x_i =1$ and by $x_j =0$, if $j\neq i$, since $x \neq 0$, then:  $0< x^TAx = a_{ii}$  But my teacher says my proof is ambiguous. How I can use the unit vector $e_1$ for the demonstration?


What does Pokémon Appraisal actually tell you in Pokémon Go?

The new update to Pokémon go brought Pokémon Appraisal to the game. The information it tells you I'm still trying to decipher. For example, when I apraise my strongest Pokémon a 1500 CP Vaporeon, I get the following information:  Overall, your Rainer is a wonder! What a breathtaking Pokémon! I see that its best attribute is its Attack. Its stats exceed my calculations. It's incredible. Your Rainer is tinier than any we have on record. Astounding.  The first line seems like just filler and the last line is already denoted by the size markings on my Vaporeon. I get the general idea that it is statistically strong and it has good attack from lines 2 and 3, but does it mean that the attack IV is perfect? How exactly do you relate the appraisal to your Pokémon's stats?


Given integers $(-a)$ and $(-b)$ why is the product positive?

I was given the assignment to find a way to explain why the product of two negative numbers is positive. If a middle school or high school student were to ask why is it true, I must show some logic explanation as to how we can get a positive number.     $$(-a)\times(-b)=(a)\times(b)$$   I wanted to talk about a video of a guy running backwards but the video itself playing backwards. When I hit play, it actually shows the guy running forward. But I can not find a logic way to explain it.   Any ideas or a way to explain this to a middle school student? I have to convince the student that this is a fact.


Convert Cannondale CAAD9 to a hybrid style...?

Can a road bike be "converted" to a hybrid/more upright bike? Flat bars and the shifters/brakes should be simple enough, but will the shifters adapt to my Ultegra set?


For any statement independent of $\mathsf{ZFC}$, can we prove it is independent of $\mathsf{ZFC}$?

Gödel's famous incompleteness theorem implies, in particular, that there are statements unprovable in $\mathsf{ZFC}$. This implies that we could never hope to settle the truth of every mathematical statement using a reasonable (r.e.) axiom system, shattering Hilbert's program. However, in the 90 years since,  have been found of statements which are independent of the $\mathsf{ZFC}$ axioms.  Is it true (or possible) that any statement in $\mathsf{ZFC}$ (or another r.e. system $\mathsf{S}$) could be proven either:   true; false; independent of $\mathsf{ZFC}$ (resp. $\mathsf{S}$)?   This would allow a weak sort of realisation of Hilbert's program: for any statement, we can either prove/disprove it, or show it is independent of $\mathsf{ZFC}$.


Is there any difference between "crenellations" and "battlements"?

Both these terms seem to refer to the jagged parapets you see on classic medieval castle towers.  Merriam-Webster  "battlement" like this:     a parapet with open spaces that surmounts a wall and is used for defense or decoration   And it  "crenellation" like this:     1   :  battlement      2   :  any of the embrasures alternating with merlons in a battlement — see battlement illustration    Looking at the picture, it appears a "crenellation" is a gap in the parapet, and a "merlon" is a solid part, while "battlement" is the whole thing.  But this doesn't seem to match up with the usage in , which says "crenellation" is the process of converting a parapet into a battlement (by knocking holes in it).  If I specifically want to talk about what Merriam-Webster calls "merlons," what is the best word to use?


Tensorflow - keras: bad performance for simple curve fitting task

I'm trying to implement a very simple one layered MLP for a toy regression problem with one variable (dimension = 1) and one target (dimension = 1). It's a simple curve fitting problem with zero noise.  Matlab - Deep Learning Toolbox  Using levenberg-marquardt backpropagation on a MLP with a single hidden layer with 100 neurons and hyperbolic tangent activation I got pretty decent performance with almost zero effort:   MSE = 7.18e-08  Here's a plot of the fitting:    This is the working matlab code. Please note that the "feedforwardnet(100)" function only produces a network object with one hidden layer with 100 neurons and tanh activation and output layer with linear activation:  net = feedforwardnet(100); net.trainParam.min_grad = 1e-25; net.trainParam.max_fail = 50; net.trainParam.epochs = 500; %net1.trainParam.showWindow = false; net.inputs{1,1}.processFcns = {}; net.outputs{1,2}.processFcns = {}; net = train(net,Train_Vars,Train_Target); Test_Predictions = net(Test_Vars); Accuracy = msemetric({Test_Predictions},{Test_Target});   Python - TensorFlow - Keras  With the same network settings I used in matlab there's almost no training. No matter how hard I try to tune the training parameters or switch the optimizer.  MSE = 0.12900154    I can obtain something better using RELU activations for the hidden layer but we're still far:  MSE = 0.0582045    This is the code I used in Python:  #  IMPORT LIBRARIES import numpy as np import pandas as pd import matplotlib.pyplot as plt import tensorflow as tf from tensorflow import keras   #  IMPORT DATASET FROM CSV FILE, SHUFFLE TRAINING SET  #  AND MAKE NUMPY ARRAY FOR TRAINING (DATA ARE ALREADY NORMALIZED) dataset_path = "C:/Users/Rob/Desktop/Learning1.csv" Learning_Dataset = pd.read_csv(dataset_path                           , comment='\t',sep=","                           ,skipinitialspace=False) Learning_Dataset = Learning_Dataset.sample(frac = 1)  # SHUFFLING   test_dataset_path = "C:/Users/Rob/Desktop/Test1.csv" Test_Dataset = pd.read_csv(test_dataset_path                           , comment='\t',sep=","                           ,skipinitialspace=False)   Learning_Target = Learning_Dataset.pop('Target') Test_Target = Test_Dataset.pop('Target')  Learning_Dataset = np.array(Learning_Dataset,dtype = "float32") Test_Dataset = np.array(Test_Dataset,dtype = "float32") Learning_Target = np.array(Learning_Target,dtype = "float32") Test_Target = np.array(Test_Target,dtype = "float32")      #  DEFINE SIMPLE MLP MODEL inputs = tf.keras.layers.Input(shape=(1,)) x = tf.keras.layers.Dense(100, activation='relu')(inputs) y = tf.keras.layers.Dense(1)(x) model = tf.keras.Model(inputs=inputs, outputs=y)     #  TRAIN MODEL opt = tf.keras.optimizers.RMSprop(learning_rate = 0.001,                                   rho = 0.9,                                   momentum = 0.0,                                   epsilon = 1e-07,                                   centered = False) early_stop = keras.callbacks.EarlyStopping(monitor='val_loss', patience=100) model.compile(optimizer = opt,               loss = 'mse',               metrics = ['mse'])   model.fit(Learning_Dataset,            Learning_Target,             epochs=500,            validation_split = 0.2,            verbose=0,            callbacks=[early_stop],            shuffle = False,            batch_size = 100)     #  INFERENCE AND CHECK ACCURACY Predictions = model.predict(Test_Dataset) Predictions = Predictions.reshape(10000)  print(np.square(np.subtract(Test_Target,Predictions)).mean()) #  MSE  plt.plot(Test_Dataset,Test_Target,'o',Test_Dataset,Predictions,'o') plt.legend(('Target','Model Prediction')) plt.show()    What am i doing wrong?  Thanks


Why is base resistor of a transistor important?

I know that this is a very basic question but I really do not know the answer.  I was making simple logic gates using transistors and I used PNP transistor as NOT gate.   I made the following circuit: (A) AND (B) AND (NOT C)   This circuit does not work without the resistors R1,R2 and R3. Why are these resistors important ?         – Schematic created using   The Following NOT gate does not need a base resistor. I connect Vcc or ground directly to base and it works.  How can it work without resistors although it is very similar to the previous circuit ?


References for intermediate cryptography

I just finished an intro course in cryptography and I found it very interesting and want to pursue it further. I wanted some intermediate-level books and resources which will deepen my knowledge of this subject. Specifically, I want to read about  stream ciphers randomness, hash functions design considerations (how symmetric and asymmetric systems are designed) cryptanalysis  Preferably, I would not want references too terse or rigorous in math but neither too computer science-y. Our class followed the book Introduction to Cryptography: With Coding Theory (Trappe, Washington) and I really liked the approach of the book and would want similar resources (in terms of how they approach topics). Any help would be appreciated.


Are the gradient field are the only fields which are only conservative?

I have found that gradient fields are always conservative. But for my knowledge I wanna ask "are the gradient fields are only fields which are conservative"?  I mean is it necessary that a field which is conservative has to be a gradient field of some scalar function?


Clear all messages from current Terminal session

In a Terminal window, if I issues a "clear" command it clears the screen.  But if I scroll up, the messages are still there.  Is there a way to clear call completely?  Currently, I have to close and reopen the Terminal again to achieve this.


Finitely generated modules over a Noetherian ring are Noetherian

I'm trying to prove that if the ring $R$ is Noetherian then every finitely generated $R$-module is Noetherian.   First of all, it is known that every module is a homomorphic image of a free module, so we can take $R$ as a module over itself, and then we will have a homomorphism $f:R \rightarrow M$, where $M$ is some arbitrary module. Next, according to the well-known theorem, $$\operatorname{Im}(f) \cong \frac{R}{\ker(f)},$$ and  $\frac{R}{\ker(f)}$ is Noetherian because $R$ is Noetherian (we can take finite set of generators for some submodule in $R$ and then its canonical image in $\frac{R}{\ker(f)}$ generates submodule there). Thus, $\operatorname{Im}(f)$ is Noetherian as well, but $\operatorname{Im}(f) \subseteq M$. How then one could say the same about the whole module $M$?


Evaluation map infinite dimensional vector space

In a finite-dimensional vector space, we have an isomorphism ev: $ V \to V^{**}$, where ev(v)$: V^* \to F$ and $f \mapsto f(v)$. But what exactly happens in the infinite-dimensional case? Why is ev$(v)$ not surjective?


Questions about dual booting and brand new SSD!

I am new to Linux (besides briefly messing around with it over 10 years ago) and I have some questions about setting up dual boot with Windows 7. Basically I am looking for the best way to get up and running so if you have other suggestions that would be better than what I list below please let me know!  So my new SSD just came about 5 minutes ago so I'll be installing that today as my boot drive. My "plan" was to install Windows 7 from my USB first and get that all set up and then after all that, partition the SSD and install Ubuntu. Is there any downside to doing it this way? Once Windows is set up do I just use the built in "Disk Management" to partition the drive or when I boot from the Ubuntu installer is there an option there to partition the drive similar to how there is when going through windows setup?  This might not be directly related but is there anything special I need to do to this new SSD before installing windows? It's my first SSD. Should I connect it as a second drive first and use Windows "Disk Management" to format it? OR just install it as my main drive and get right to installing windows? Or should I install it as my second drive and partition it first thing with Disk Management?   As you can see I'm not sure of the best ways to set this all up or if it even really matters. Any input would be appreciated of what is the best way to go about this and why it's better than another way.  Thank you!!


Does a person make a profit when the bid price is higher than what was originally paid for the share? I know that you buy the ask, sell the bid, but if I ask to sell a share at a higher number than what I paid for it, especially if the share is appreciating in value, do I stand a higher chance at making a profit?


As I understand it, the concept of reputation is to give the user a sense of trust in the person answering the question.   On that note I find many users who's reputations are very high, but its from asking questions and getting up voted and not from providing other users with answers. At this point it is misleading unless you go to the users profile and investigate where their reputation is coming from.  Should there be a split between, answering reputation and asking a question reputation?  just throwing it out there.  EDIT:  i did not say to entirely get rid of reputation from asking questions.  I am merely suggesting a separation in the two. A reputation for answering and a reputation for asking good questions. This way you can differentiate quickly.  If its strictly for the system, then why display it after each users name?


How to prove the following inequality (with a introduced constant $\lambda$)?

Suppose that $X$ is a positive random variable, with expectation $\mu$ and variance $\sigma^2$. Prove, for all $\lambda\in(0,1)$, we always have $$P(X>\lambda \mu) \geqslant (1-\lambda)^2 \frac{\mu^2}{\mathbb{E}[X^2]}$$ Can someone sort out the proof using Chebyshev's inequality? Thanks very much.


Area of parallelogram = Area of square. Shear transform

Below the parallelogram is obtained from square by stretching the top side while fixing the bottom. Since area of parallelogram is base times height, both square and parallelogram have the same area.    This is true no matter how far I stretch the top side.    In below figure it is easy to see why both areas are same.   But it's not that obvious in first two figures. Any help seeing why the area doesn't change in first figure?


Coding categorical variables for regression

I'm not sure of the best way to code my categorical predictor variable for use in a hierarchical regression in order to test my specific hypothesis. This categorical variable has 3 levels representing 3 groups. I want to compare group 1 to group 2, group 1 to group 3 and group 2 to group 3. I know that for dummy coding I create k-1 variables, so 2 dummy variables in my case and code these variables with 0s and 1s while choosing one level of the categorical variable to be a reference category.   However, I'm not sure this is the best way of making the comparisons I wish to make as it appears I could only compare each group to the reference category, am I correct? So if group 3 was the reference category I could compare group 1 to group 3 and group 2 to group 3 but I could not compare group 1 to group 2. What alternative method of coding should I use to make these comparisons? My regression model will also contain continuous variables. I'm an undergrad psychology student and statistics are not my strong point simple answers would be best for me. I use SPSS. Thank you!


What does the red R in old manual lenses mean?

This lens for example:   It has a R between the hyperfocal markings. What does that mean and how can I use it?  Note: To those who said this  is the same question as mine, the link questions about Red values and that's for modern lenses while there is no Red value in vintage lenses as you can see in the picture above, there is just a single R


I am trying to install git-lfs package and it looks like expected paths are not Ubuntu friendly. From  I choose Linux AMD64 file name git-lfs-freebsd-amd64-1.2.1.tar.gz, because .deb files are not available for Ubuntu, just Debian 7,8.  I am getting error: install.sh: 19: install.sh: PATH+=:/usr/local/bin: not found when executing install.sh.  Does anyone have a working solution on how to install git-lfs?


Let $(X, A)$ and $(Y,B)$ be two measurable space. Let $f \geq 0$ be measurable w.r.t $A \times B$ (product $\sigma$ -algebra). Let $g(x)=\sup_{y \in Y} f(x,y)$ and suppose $g(x)< \infty$ for each $x$. Is g necessarily measurable w.r.t $A$?   I am not sure whether the answer is no or yes. But, I haven't been able to produce a proof. Thanks in advance for any help!


how to compute $\gcd(\frac{a}{b},\frac{c}{d})$?

is there a formula for   $gcd(\frac{a}{b},\frac{c}{d})?$  I'm conjeturing $gcd(\frac{a}{b},\frac{c}{d})=\frac{gcd(a,c))}{lcm(b,d)}$ but how to prove it?


Boolean Difference doesn't work despite all efforts to fix meshes

I am trying to carve a groove into an object. This works with other objects after some mesh fixes but not with this one, which was created using a surface nurbs curve (duplicated multiple times, then skinned and converted to a mesh)  The boolean difference modifier does not modify the mesh at all.  I already tried the following steps on both meshes: Triangulate, Remove doubles, Recalculate normals (both outwards), Fill holes.  The thing I don't understand is that when I select "Intersect" in the boolean modifier to check where the overlap is, I don't get a solid object but an open one:  What am I missing here? Any help would be greatly appreciated.  Here is the blender file (created with V 2.78c)


Defining list with 'enumerate' explanation

I came across this useful bit of code that returns the indexes of the minimum values of a list l  [i for i, x in enumerate(l) if x == min(l)]   Could someone help me with what this way of creating a list is called and/or what the process is? I'm familiar with [i*2 for i in l] type code but I'm not familiar with what the comma does and what the reason for defining a new variable x is.  Many Thanks


Are undefined terms allowed in a sequence?

Is this a valid sequence: $$\left\{\frac1{(n-3)}\right\}?$$ That is, can a sequence have individual terms that are undefined? If so, does this mean that the above sequence is unbounded (since the third term is not smaller than any real number)? [What I do know is that if the above sequence were valid, it would be convergent (by definition), which would in turn mean that it is bounded (by the Boundedness Theorem).]  Subsequent to the main discussion here, I have just come across an old exam question that asks us to show that $\langle\tan(\frac{\sqrt n\pi}4):n∈N\rangle$ is divergent. But this sequence is undefined at say, $n=4$, so like the one above, it isn't even a valid sequence, is it? (I've used a different notation for sequences on Brian M Scott's advice.)


How to turn off subsurf modifier on a lot of objects at the same time

I have a model containing about 30 objects, all together about 900,000 vertices. My computer can't handle this amount of verticies and it gets realy slow. Is there a way how to turn on/off subsurf to all these objects at the same time?


my if - then statement results to false even though the condition is true  I've tried casting values to doubles      dblCompare = CDbl(rng1.Offset(0, -12).Value2)     If dblTotal = dblCompare Then         'If the values match, then record the Unique IDs in Columns AI:AN         Range(Cells(m, 35), Cells(m, 35 + k - 1)) = arr     End If   dblCompare = 114954.48 and dblTotal = 114954.48.  However, the statement results to false and the pasting of the array into the Range is completely skipped.  Sometimes the if-then statement results to true and the contents of the array is pasted into the range, but sometimes it doesn't.  VBA appears to be very buggy.  All I can think of is that dblCompare needed to be type cast to a Double.  My declarations:   Option Explicit Sub Find_Recs()     Dim i As Integer, j As Integer, k As Integer, m As Integer     Dim strSearch As String     Dim dblTotal As Double, dblCompare As Double     Dim rng1 As Range, rng2 As Range     Dim arr As Variant ' ' 'code here ' ' End Sub


Why does my question not meet your quality standards?

I want to ask a question on Stack Overflow, but when I post the question I get this error in a red box:     This question body does not meet our quality standards. Please make   sure that it completely describes your problem - including what you   have already tried - and is written using proper grammar.   My question body:     When i merging 2 drives in win7, at the middle of merging my computer   turned off (power unplugged).   Now i have the made drive. and i can see all folders and files of two   drives when i using Explorer but i can't opening any file of this   drive!   can you help me to recover files contents? can i repair filesystem or   reformat drive without lost files?   Why does this not meet your quality standards, and what can I do to address this?


workspace switching via ctrl + alt + arrow not working after upgrade to 13.04, how to fix this?

So, my update to 13.04 didn't go very well. Due to the lack of a decent driver (Yes, i'm unlucky to have a legacy driver which doesn't play nice with the new Xorg.), I had to mess around with stuff to first troubleshoot and afterwards "fix" my system.  I've finally got unity back, but now CtrlAltarrow and CtrlAltShiftarrow don't work anymore. They are bound in "keyboard" > "shortcuts", but nothing happens when I try it. A strange thing is that other keyboard shortcuts, like ctrlaltt to show terminal are still working.  I noticed that CtrlAltarrow doesn't show in the list with "unity shortcuts" (the list that shows when you hold the super key).  Does anyone know how to re-enable this way of workspace switching?  I enabled workspaces in the appearance menu. It doesn't have any effect though. Switching via the workspace-switcher in the unity dash works fine though.  CCSM is installed, but I can't seem to find a way to add keyboard bindings there.     System: ubuntu 13.04 64bit


How to move to the ux from industrial design?

Just found this site and it's my first question. Bit of a long story, but I think most of it is relevant considering the question. (If you are in a hurry, you can jump straight to the questions)  So. I'm an industrial design student, and it's my second year going at the moment. What has to be mentioned as well is that I'm not an average id student fresh from the high school, I'm 31 and I have studied business master's before, though didn't graduate from it because of some personal life stuff and the financial crisis happening at the same time.  After some difficulties in personal life and in the job market I decided I'd study industrial design, as it happens that during 2008 I was working in a long project in an industrial design agency, and I liked it hugely. However because of the financial crisis the project couldn't be continued anymore in 2009. What I was doing there was in essence ux design. Then, after the financial crisis I came to find out that in this new job market, with the business studies background it was impossible to get any kind of creative design jobs, at least in my own country, I then decided to go to study industrial design. Which was probably not the best choice, I guess I should have chosen Human-Computer Interaction. But this is a small country, and HCI isn't even taught but in two different places, I think.  Fast forward to this day. In this country it seems industrial/ product design agencies never really recovered from the financial crisis. Most of them don't do cutting edge tech projects but instead they have put their heads in sand like ostrichs. They do mostly very traditional industrial design, without any interaction or user experience design. Which is a really bad situation for me personally, because the reason I got into ID was that I want to work in creative usability and UX projects.  Anyhow, there is a lot happening in UX scene in this country. But it's happening in mid sized software companies, and in these new, specialized small UX agencies, which are coming from the HCI side of the business, if I have understood right.  So now the big questions for me are:   How do I get into this new UX design scene, with my background?  How do I get a job or an internship in one of these companies which don't really know too much about ID, and probably think that ID is nothing but pretty and very concrete products?   What kind of stuff should I do into my portfolio?  What kind of stuff should I emphasize in my CV and cover letter?  What kind of things should I study by myself?  Would studying HTML and CSS be the shortest way to UX design for me?  What I personally consider important in my skills and knowledge is that I have been interested in usability and UX already for years, and have read for example Don Norman's books, as well as some basic interaction design materials. And in my previous business studies I studied many courses of sociology as a minor.  Thanks if you had patience to read it until here, and thanks even more for any answers!


I am trying to make my nginx redirects as clean as possible.  I understand ~* is for case insensitive but I can only get it to work in example 2.    Example 1  rewrite ^/foobar http://www.youtube.com/watch?v=oHg5SJYRHA0 redirect;   Example 2 -This works, but it isn't as efficient as the line above.     if ( $request_filename ~* foobar ) {          rewrite ^ http://www.youtube.com/watch?v=oHg5SJYRHA0 redirect;    }   Is there a way to do case insensitive redirects with example 1 without getting it too muddy?  Thanks.


How do I plot $-\frac{\pi}{2} \leq \operatorname{Arg}\left(\frac{z}{\bar{z}}\right) \leq\frac{\pi}{2}$ on the complex plane?

I'm new to Complex numbers, so I don't know a lot about them yet.  How do I plot this condition on the complex plane?  $$-\frac{\pi}{2} \leq \operatorname{Arg}\left(\frac{z}{\bar{z}}\right) \leq\frac{\pi}{2}$$


How to get the Date and Time of Current Location in Python

I want to get the Date and Time of The Current Location. If somebody runs the code in a different country thought it will show the date and and time for them, and not for me. If you know any commands for this please put the down bellow. I prefer If I don't need a library so that people who get the code don't need to download the library.


Referring to correctly-styled algpseudocode procedure name in document

Given an algorithm written in algpseudocode:  \documentclass{article} \usepackage{algorithm} \usepackage{algpseudocode} \begin{document} \begin{algorithm}   \caption{Part 1}   \begin{algorithmic}[1]     \Procedure {FooProc}{$G$}       \State ...     \EndProcedure   \end{algorithmic} \end{algorithm} \end{document}   How can I now refer to FooProc in my document (outside of the algorithm environment) such that it has the same typeset as in inside the algorithm environment?


Deep learning classification satellite/airbone images in R?

I am looking for tutorials and guides to learn deep learning in remote sensing images (satellite imagery, ortophoto from airbone) in R, because I already know it quite well and would like to stay with R. I have seen that someone already searched for an answer to this question 3 years ago, but did not find it. Therefore, I would like to repeat this question because I hope that something has changed.


Back To The Future: Why should Marty fade at all?

Other threads have posed the existence of "meta-time" at right-angles to ordinary time, allowing for a single universe in which time can be changed, but resolving the paradoxes. On that basis, however, why should Marty have begun to fade at all, since he comes from an "earlier" point in meta-time? Surely he should continue to exist, as although in the future where George and Lorraine never get together and the McFly kids are never born, Marty comes from an earlier meta-time, in the 1967 or 1968 of which he was born?


Are airlines in the EU obligated to provide water for passengers?

I was flying with Ryanair last month and wanted to take some vitamin pills while on board. I went down to the end of the plane and asked for a glass of water, but the stewardess refused. Since the only other option was to buy a 3EUR bottle, I've decided to take the pills later.   Is there some EU law which obligates airlines to provide water while on board? What about if someone needs water to take their medicine?


What does the 5 mean when a damage roll is 5 (1d6+2)

I'm teaching myself 5e from absolute scractch, and I'm trying to roll an attack with a shortbow. AC modifiers + initiatives are fine, but calculating the actual damage is something that's tripping me up.  Does '5(1d6+2) piercing damage' mean Roll 1d6 + 2 for a maximum of 5 damage or something else entirely?  Thanks!


How do you disable a service in systemd?

I know what the command is sytemctl disable NAME but I have a question about the NAME parameter.  For example the bluetooth service[1] on Fedora 21. For the NAME parameter should you put bluetooth or bluetooth.service or bluetooth.target?  Please note I am using bluetooth as an example but the question is meant to be generic (i.e. if a service has many associated units (i.e. socket, target, service)).    [1] When I searched for the bluetooth service I found a couple things that matched the "bluetooth" grep string:  $ systemctl list-unit-files|grep -i bluetooth bluetooth.service                           enabled  bluetooth.target                            static


Understanding how inputs are sent to pipes in Bash

I dont quite understand how pipes work in bash.  I know that it takes an output from one command as the input in another command.  What an output is I can get because it's what the command prints out to the screen.  But how do I know what input a command will take?  Here is an example I thought would work:  which gem | rm   Unfortunately it didn't.  Which gem prints out /usr/bin/gem so that must be the output right?  I thought that was given to rm so it woud be rm /usr/bin/gem but I was wrong.  So my question is, how do I know what input a command takes?


Ubuntu Core/Snappy affected by Meltdown and Spectre?

Will Core/Snappy 16.04 and later need to be fixed for amd64 images as well, or does this just apply to desktop and server editions?


Combine two textures in OBJ into single texture

I have an OBJ file that has two meshes mapped to two different texture files.  After cropping the meshes in Blender, I realized that most of the original image portions in the texture jpegs are not being used.  Hence I want to combine two textures into a single texture and export the meshes into a OBJ file.  How can I do this in Blender?


Minimum value - Extension of Triangle Inequality?

What is the minimum value of  $|x-1| + |x-2| + |x-3| .... + |x - k + 1| + |x-k|$ equal to?  I suppose it depends on whether or not $k$ is even or odd.   I was able to solve for $k = 3$ (three terms) using the triangle inequality - but couldn't generalize it to the above. Please help.


Remove weird default starting characters in minted

Problem  I am trying to typeset my code using package minted. However, when I chose the default setting (where showspaces and showtabs options are both false by default), some characters (i.e. ^^I)seem to be indicating spaces are shown.   Note the in the following minimal example, the printf("hello, world"); and return 0; are intentionally made to show the aforementioned effects.  \documentclass{article} \usepackage{minted}  \usepackage[margin=0.5in, nohead]{geometry}  \begin{document} \begin{minted}[linenos=true, showtabs=false]{cpp} int main() {     printf("hello, world"); return 0; } \end{minted}


How to Remove Specific lines From a text file?

I had made some progress with this  code going through the while loop giving me all the lines of a text file but I keep getting a reoccurring error called java.io.nullException.   public static void main (String[] args){ Msg msg = c.element(); String line = msg.getLine();  Map<String, String> attributes = msg.getAttributes(); ArrayList<String> list = new ArrayList<String>();  try {  BufferedReader file = new BufferedReader(new FileReader("pro.txt"));  String line;   while ((line = file.readLine()) != null)   Pattern regex = Pattern.compile ("[^\\s\"]+|\"[^\"]*\""); Matcher regexMatcher = regex.matcher(line); while (regexMatcher.find()) { String match = regexMatcher.group(); match = removeLeadingChar(match, "\""); match = removeLeadingChar(match, "\'"); list.add(match); } System.out.print(line);


Mysql Pivot rows into dynamic columns with unknown number of columns

I have an output of a query as follows:  bid  | code | amount        | ----------------------------- 2915 | BF   |   -10700.00   | 2915 | YQ   |   -300.00     | 2915 | YR   |   0.00        | 2915 | YM   |   0.00        | 2915 | WO   |   -153.00     | 2915 | IN   |   -329.00     | 2915 | K3   |   0.00        | 2915 | CUTE |   -50.00      | -----------------------------   I need to convert the values in code column to individual columns with column name as corresponding code and amount shall be the value.  bid  | BF       | YQ     | ... | CUTE  | ---------------------------------------- 2915 | -10700.00| -300.00| ... | -50.00|   The issue is that the result of my initial query has dynamic codes and hence need to generate columns accordingly.  Already tried the following logic but couldn't achieve the goal:   , ,   All the above links use some expression or the other to generate the columns.   My original resulting rows are result of simple select on multiple joined tables, and has no calculation or expression scope.  Kindly suggest some pointer or hint on how to achieve this.  Many thanks in advance.


How to detect player joining a Minecraft world?

I'm making a 1.12 map that need to do something when a player join. I tried stats.leavegame method, but if the game crashed the last time, the command won't run.  No file permission for it's hard to share, but unintended file type (like using a file to take the place of a folder, in my answer) is fine


Reactivating “\clearpage” in LaTeX after turning it off with “\let\clearpage\relax”

My document has a table of content in it. As i found out, after inserting one (\tableofcontents) LaTeX does a \clearpage by default.  A method to ignore \clearpage is the command \let\clearpage\relax, witch ignores it till the end of the document. Although i have no other command in my doc, my last page got erased. So i want to reactive \clearpage right after the toc was generated.  I am searching for something like:  \let\clearpage\relax \tableofcontents \*reactive it*   One try to do it with \begingroup failed.  \begingroup \let\clearpage\relax \tableofcontents \endgroup   Any ideas?


I received an email this morning stating that my Wordpress site had been automatically updated to the latest version. I knew about the feature but I've always wondered exactly how it works.  PHP isn't a permanently-running process: it only runs when requested. So as far as I can tell, Wordpress can only update itself when someone loads a web page. But the update process is not instantaneous, so surely a user visiting the site would have a really slow page load.  Is there a different trick they use for automatic updates? I've searched all over the place but haven't found any explanation.


My question is the following: We have two 220V 20A generators connected in parallel to total power 8.8 kw 220 v 40 A load  is 5.5 ohms I'm interested how each generator sees this load since every generator gives half the power. I put this question because one generator can not see this load like 5.5 ohms because it gives half power to not the full power I would like to have somebody explain it a little bit better because it makes me confused .     simplified question   my question is that since every generator in the parallel circuit gives half power in the ideal case it would mean that the generator 1 that gives 220v 20A that is half the power can not "see" the resistance of 5.5 ohms because if "seen" this resistance he had to give complete current in that case we have two problem generator 1 burned because it is not made for such a current problem two if generator 2 gives the same current then the law on energy conservation is not worth what is absolutely not possible  thanks    The last attempt to explain what I asked is very simple  we have two 220v 20A generators and a load of 5.5 ohms if we connect this resistance to just one generator it exceeds its power because it is 220v and 20 A 4.4 kw and the current at that resistor is 40A which would mean that it exceeds the maximum power of one generator ok if we add another generator then together have enough power to supply load it if we know that every generator gives half power ie 220v and 20A  it is impossible to "see "a resistance of 5.5 ohms


Does a non-clustered index make any guarantees about row order?

I have a developer that would like, when doing a select statement with no order by, the rows in a table to be in the order they were inserted. The developer suggested changing from a clustered to non-clustered index.   By changing the index from clustered to non-clustered, does this make any guarantees about the order in which rows would appear in the table?  This question is mostly for my curiosity; I am going to suggest using an identity column instead, but this request got me thinking. Timestamp could be used but there is a chance rows can be inserted simultaneously.   Thanks in advance for your help.


I recently found a question on superuser regarding ejecting a CD using the Windows command line.  How can I do this using Linux terminal?


How to safely upgrade from an older Ubuntu version to a newer one?

How can I safely upgrade an Ubuntu installation from one release to another? What should I do before upgrading to ensure it goes smoothly, and is there any clean-up I need to do afterwards?  In particular, do I need to do anything special if I am using packages from PPAs, if I have a graphics card that needs drivers, or if I'm running a custom Linux kernel?  This is a general question , but as example we take Ubuntu 12.04 and Ubuntu 12.10


Let hover on vote arrow explain vote lock

Current behavior  When you hover over the arrow after you already voted over 5 minutes ago, it explains that you can "click again to undo":    However when you click on it, you get the vote lock error:    Expected behavior  Let the hover message display the current error message since you can't actually "click again to undo". Possibly explain that the undo window is 5 minutes.


What static analysis tools are available for C#?

What tools are there available for static analysis against C# code? I know about FxCop and StyleCop. Are there others? I've run across NStatic before but it's been in development for what seems like forever - it's looking pretty slick from what little I've seen of it, so it would be nice if it would ever see the light of day.   Along these same lines (this is primarily my interest for static analysis), tools for testing code for multithreading issues (deadlocks, race conditions, etc.) also seem a bit scarce. Typemock Racer just popped up so I'll be looking at that. Anything beyond this?  Real-life opinions about tools you've used are appreciated.


Is missing later flight in connecting flight possible?

Has anyone traveled with connecting flights and skipped the other flight will there be any issues.  for instance: my ticket is from: Bangalore -> Mumbai -> Delhi (no return ticket) and what if I skip the Mumbai -> Delhi flight, will there be any issues in my future travel ??  PS.: I will only be taking hand baggage so no issue for baggage being directly sent to final destination.


Creating multiple rows from one row of Excel Data

My data looks like this:  Parameter   Location_A   Location_B   Location_C  Location_D  A           1            0.3          0.2         0.1 B           0.9          0.3          0.1         0.1 C           1.1          0.2          0.3         0.2   I have 365 parameters and 768 locations.  I want to create one row for each parameter and location combination and show the results in a third column (i.e., 365*768 = 280,320):  Location       Parameter     Result Location_A     A             1 Location_A     B             0.9 Location_A     c             1.1 Location_B     A             0.3 Location_B     B             0.3   And so on.  Is there an easy way to do this?  I have a header row and then 365 rows for each parameters and column B thru ACO are locations.  I've looked through a few things but cannot seem to find the answer:


How to make a proper star effect in Blender

Is there anyone who can help me create a photorealistic star effect along the lines of this test video:    If you missed it, here's a screenshot (it's the blue one in front):    I'm aiming to get my star to be exactly like the front light blue one featured there in - a six pointer with thinner, sharper lines as opposed to the broader and more easily faded ones you usually get when you apply the glare effect.


Java generic: why type erasure won't allow check instance of generic

I read  about why Type erasure makes java less powerful then some languages in generic. In wiki page, here is one example:  public class MyClass<E> {     public static void myMethod(Object item) {         if (item instanceof E) {  //Compiler error             ...         }         E item2 = new E();   //Compiler error         E[] iArray = new E[10]; //Compiler error     } }   I understand why E item2 = new E(); should be compiled error because we really don't know class E before calling them. But I don't know why this line should be error:  if (item instanceof E) {  //Compiler error    ... }   Because as I know, when compiling java application, all generic type will replaced by its concreted type. for example:  // all E will be substituted by Integer  MyClass<Integer> myObject = new MyClass<Integer>();    So I don't think why should Java throws compile error at above line.


curl with Umlaut causes "JSON parse error: Invalid UTF-8 middle byte 0x22"

I'm running below curl command from the command line (Git Bash on Windows) or as part of a Bash Script.  curl -s -X POST -H "Content-Type: application/json" -H "Accept: application/json" -d "{\"testField\":\"ä\"}" https://someurl...   The body of the curl command has an Umlaut ä.   The server which is a Spring Boot REST API running in an AWS Elastic Beanstalk Container returns the following error:   JSON parse error: Invalid UTF-8 middle byte 0x22; nested exception is com.fasterxml.jackson.core.JsonParseException: Invalid UTF-8 middle byte 0x22\n at [Source: (PushbackInputStream); line: 1, column: 17]   The same curl command imported into Postman works just fine, so I believe it's rather a curl issue than a server problem.


Difference between BYTE and CHAR in column datatypes

In Oracle, what is the difference between :  CREATE TABLE CLIENT (  NAME VARCHAR2(11 BYTE),  ID_CLIENT NUMBER )   and  CREATE TABLE CLIENT (  NAME VARCHAR2(11 CHAR), -- or even VARCHAR2(11)  ID_CLIENT NUMBER )


How to load a .NET assembly for reflection operations and subsequently unload it?

I'm writing a tool to report information about .NET applications deployed across environments and regions within my client's systems.  I'd like to read the values of assembly attributes in these assemblies.  This can be achieved using Assembly.ReflectionOnlyLoad, however even this approach keeps the assembly loaded.  The issue here is that I cannot load two assemblies that have the same name from different paths, so naturally I can't compare the same application deployed in different systems.  At this point I'm assuming the solution will involve using temporary AppDomains.  Can someone detail how to load an assembly into another AppDomain, read the attributes from it and then unload the AppDomain?  This needs to work for assemblies on the file system as well as those at URL addresses.


How Prove this $ \sum\limits_{k=1}^{2n} { 2n \choose k } { 2n \choose 2n-k } = 2^{4n} - 1$

$$ \sum_{k=1}^{2n} { 2n \choose k } { 2n \choose 2n-k } = \binom{4n}{2n} - 1$$  This equation have nice methods?  Thank you everyone,   This problem is from this


What’s the difference between "I have known her since/for a long time"?

What’s the difference between these two:   I have known her for a long time. I have known her since a long time.   I think that the first one says that we have been friends for a long time but we broke our friendship recently, but that the second one says that we have been friends since a long time and our friendship still continues?  Is this accurate?


What is meaning of #import? if we use #include what happens?

Why use #import in objective c? if we use #include what happens?


I am using Ubuntu 16.04. I am doing copy and paste of large data from one drive to another. It took over 30 minutes.  When I am trying to see the status using right click to see show copy dialog nothing is happening.  I tried by double clicking on File Manager but no success.  Any idea?


False proof that $ρe^{iθ} = ρ$ and so complex numbers do not exist?

My professor showed the following false proof, which showed that complex numbers do not exist. We were told to find the point where an incorrect step was taken, but I could not find it. Here is the proof: (Complex numbers are of the form $\rho e^{i\theta}$, so the proof begins there) $$\large\rho e^{i\theta} = \rho e^{\frac{2 \pi i \theta}{2\pi}} = \rho (e^{2\pi i})^{\frac{\theta}{2\pi}} = \rho (1)^{\frac{\theta}{2\pi}} = \rho$$ $$Note: e^{i\pi} = -1, e^{2\pi i} = (-1)^2 = 1$$ Since we started with the general form of a complex number and simplified it to a real number (namely, $\rho$), the proof can claim that only real numbers exist and complex numbers do not. My suspicion is that the error occurs in step $4$ to $5$ , but I am not sure if that really is the case.


How to install Bad Piggies on ubuntu 12.04?

I am completely new with Wine. I haven't installed any games through Wine. What are the steps to install  on Ubuntu 12.04?


How to prove that $ a^2+b^2+c^2=1$ implies $ab+bc+ca \in [-\frac12,1]$?

If $a,b,c$ belong to set of real numbers and $ a^2+b^2+c^2=1$ then prove that $ab+bc+ca$ belongs to $[-\frac12,1]$  I have tried AM>GM>HM(progressions mean inequality) but I am unable to do anything. I have even attempted to assume a,b and c to be sides of an triangle and using $|a-b|<|c|$ and squaring but still I don't get the right-hand limit right.  Please tell me how to prove it.


How do I use multiple bibliography styles

e.g. I want to use bibliographystyle{unsrt} to do the referencing as per order of appearance along with bibliographystyle{abbrv} to abbreviate the names of the autho. Is this possible?


NullPointerException when iterating over a two dimensional array of objects

I'm running tests for my board class in a game I am making, and continue getting a nullpointerexception when I try to search for an object in my array.   public class Board extends java.util.Observable{  //10x10 array that holds the tokens private Token board[][];  /**  * Constructs board   */ public Board(){     board = new Token[10][10]; }  /**  * Adds token to the board at the location that the token is  * @param token     token to be added  */ public void addToken(Token token){     Location loc = token.getLocation();     board[loc.getX()][loc.getY()] = token;      //notifies view that it needs to redraw the board     notifyObservers(); }  /**  * move token that is already on the board  */ public void moveToken(Token token){     //checks if the piece is in the board     boolean moved = false;      //finds piece     for(int i = 0; i < board.length; i++){         for(int j = 0; j<board[i].length; j++){             if(board[i][j].equals(token)){  //THIS IS THE LINE THAT CAUSES THE ERROR                 board[i][j] = null;                 moved = true;             }         }     }     //if piece is not on board, throw error     if(!moved) throw new GameError("Attempted to move token that is not on the Board");      //add the token in its new location     addToken(token); }   The exception is caused in the moveToken method, which I call in the following test.      @Test  public void testAddToken(){     Board b = new Board();     Token[][] board = b.getBoard();     Token t = new Token('a', "a....", true);     t.setLocation(new Location(4,4));     b.addToken(t);     board = b.getBoard();     assertEquals(board[4][4],t);     t.setLocation(new Location(2,1));     b.moveToken(t); //THIS IS WHEN THE ERROR IS CAUSED     assertEquals(board[2][1],t); }   I added some System.out.print tests to check when exactly the error is caused, and it happens on the very first loop, when both i & j are zero.   Thank you in advance for any help!


Cannot killed spawned Ender Dragon with sword in 1.10.2

He doesn't move at all and I can't hit him, just random particles appear. How do I remove it?


Is it possible within SFDC to identify which reports are using a specific object?  I would like to obsolete the reports but don’t know how to identify short of looking up each individual report


Differentiable function, with $f'(x)=[f(x)]^2$

Let $f: \mathbb{R} \to \mathbb{R}$ be a differentiable function such that $f(0)=0$ and $\forall x \in \mathbb{R}$, we have $f'(x)=[f(x)]^2$. Show that $f(x)=0, \forall x \in \mathbb{R}$.


How do I make an item where when a player holds it, it runs a slash command or function in a Minecraft bedrock addon?

I am trying to make a paintbrush to assist me and my friends build a city.  My idea for the paintbrush is when held, it uses raycasting to place blocks where the entity is looking.  I can't use scripting because one of my friends is on Xbox and can't use scripting for some reason.  For the raycasting, I'm using a mcfunction.  How do I run a slash command or function when a player holds a specific item in Minecraft bedrock?  I think it's possible because it says in the Minecraft addon documentation entity events can call slash commands, other entity events, and MoLang.  I'm attaching a picture of that section of the documentation so you can see what I mean.  Here is what the image says in case the image fails to load.  Events Events consist of three categories, all represented by a string:  Entity events Slash Commands MoLang Expressions  In detail: Entity Events: Server side (behavior packs) only. Currently, we only support entity events to self, and these take the form "@s event". These are events declared in the events section of the entity definition file. For example, in the cat.json, "minecraft:ageable_grow_up" event causes the kitten to grow up. This would take the form of "@s minecraft:ageable_grow_up" Slash commands: Server side (behavior packs) only. Any slash command can be invoked, such as /particle minecraft:example_smoke_puff ~ ~ ~. The assumed entity for the slash command is the invoking entity, so this particular slash command will spawn a smoke puff effect at the entity's location. MoLang Expressions: This executes a MoLang expression. The primary usage is to set MoLang variables that can be used later. For example, a state transition might be looking at a particluar MoLang variable, and this expression could change that variable. A particle effect on the entity might change color due to MoLang variables that the effect uses for color tints. An animation to move an arm might use a MoLang variable that was set by an animation event. // entity event (behavior packs only), put the particular event name` after the @s "@s minecraft:entity_event"  // slash command (behavior packs only), can be any server-side slash command // is invoked from the entity, so a teleport, for example, will teleport the entity by default "/tell @a this is a message"`  // MoLang Expressions, executes a molang expression on the entity "variable.something_to_set = 3;"   Am I misunderstanding?  If not, how do I do this?  If any of this is unclear to you please ask questions in the comments.  Thanks!


assume  $$x_n=\frac{n+1}{2^{n+1}}\sum_{k=1}^n\frac{2^k}{k} ,n=1,2,.....$$  how compute $\lim_{n\to +\infty}x_n$?  Thanks for any hint


How to disable mouse support in terminal?

I'm asking this question while using xfce4-terminal, but I'm interested in a general solution: is there a way to stop a terminal emulator announcing mouse support in consoles? I need mouse-select and copy-paste much more frequent that I need mouse support in vim or wherever.


I can't figure out what's wrong with my code but it fails at deletion of PS in the following [null, null, null, PS]   /**  * Removes the specified string from this hash table       * (if the string is in this table).      */ public void delete(String s) {     // TODO     int k = 0;     for (int i=0;i<M;i++) {         if (keys[i] != null) {             if (keys[i] == s) {                  k = i;         }         }     }     keys[k] = null;     for (int i=k;i<M;i++) {         if (keys[i+1]!=null) {             keys[i] = keys[i+1];         }     }     N--;       // halves size of array if it's 12.5% full or less     if (N > 0 && N <= M/8) resize(M/2); }


How to combine several models in one forms in django?

I am having 4 models in Django: Products, Orders,lines_Orders, and Invoice. Based on these models, I would like to create a form that will generate the invoice given an order number. But I don't know how the views could be and how to combine these models into one form.  class Product(models.Model):     # productId=models.IntegerField(auto_created=True)     customerId=models.ForeignKey(Customers, on_delete=models.CASCADE)     productNumber=models.CharField(max_length=15, unique=True)     productDescription=models.CharField(max_length=25)     unitPrice = models.FloatField()     storageQuantity=models.FloatField()  class Orders(models.Model):     orderID=models.AutoField(primary_key=True)     customerID = models.ForeignKey(Customers, on_delete=models.CASCADE)     oderDate = models.DateTimeField()  class Order_lines(models.Model):     oderID = models.ForeignKey(Orders, on_delete=models.CASCADE)     productNumber=models.ForeignKey(Product, on_delete=models.CASCADE)     quantity = models.FloatField(default=0.00)  class Invoice(models.Model):     dateInvoice=models.DateField()     receiveDate=models.DateField()     OrderNumber=models.ForeignKey(Orders, on_delete=models.CASCADE)   Please assist


Should an ID go at the beginning or end of the URL for SEO?

Says I have a link, which contains the ID = 19963307  Type 1 :   http://stackoverflow.com/questions/19963307/how-to-install-asp-net-mvc-5-on-a-server   Type 2 :   http://stackoverflow.com/questions/how-to-install-asp-net-mvc-5-on-a-server-19963307   Which one of the above links is better for SEO, or are they the same?


I got this problem from my teacher as a optional challenge. I am open about this being a given problem, however it is not homework. The problem is stated as follows. Assume we have an infinite tetration as follows $$x^{x^{x^{.^{.^.}}}} \, = \, a$$ With a given $a$ find $x$. The next part of the problem was to discuss the convergence radius of a. If a is too big or too small the tetration does not converge. Below is my humble stab at the problem.  My friend said you would have to treat the tetration as a infinite series, and therefore could not perform algebraic manipulations on it before it is know whether it converges or diverges. However my attempt is to first do some algebraic steps, then discuss the convergence radius. I) Initial discussion At the start it is obvious that the tetration converges when $a=1$ (just set $x=1$) Now after some computer hardwork it seems that the tetration fails to converge when a is roughly larger than 3. II) Algebraic manipulation $$ x^{x^{x^{.^{.^.}}}} \, = \, a$$ This is the same as $$ x^a \, = \, a$$ $$ \log_a(x^a) \, = \, \log_a(a)$$ $$ \log_a(x) \, = \, \frac{1}{a}$$ $$ x \, = \, a^{\frac{1}{a}}$$ Now, if we let $a=2$ then $x = \sqrt{2}$. After some more computational work, this seems to be correct, which makes me believe this formula is correct. III) Discsussion about convergence By looking at the derivative of $ \displaystyle \large a^{\frac{1}{a}} $ we see that the maxima occurs when $a=e$, which also seems to correspond to the inital computational work. Now I think, that the minima of $\displaystyle \large a^{1/a}$ is zero by looking at its graph, studying its derivative and the endpoints. So that my "guess" or work shows that it converges when $$ a \in [0 \, , \,  1/e] $$ VI) My questions Can my algebraic manipulations be justified? They seem rather sketchy taking the a`th logarithm and so on . (Although they seem to "magically" give out the right answer) By looking at Wikipedia it seems that the tetration converge when $$ a \in \left[ 1/e \, , \, e \right] $$ This is almost what I have, why is my lower bound wrong? How can  I find the correct lower bound?


Email Deliverability on Yahoo is very poor. Any suggestions please?

All other ISPs (Google, AOL, Hotmail) are fantastic, hitting 98-100% in the inbox. Yahoo is very random, and lately our deliverability has dropped drastically. All IPs are senders certified by Return Path and supposedly that automatically whitelists our IPs and allows us to send as many emails as we want (from what my boss says).  Do I bother with applying to Yahoo's bulk sender form?   I run every email campaign through:   SpamAssassin (Excellent Scores) Test Accounts (for test deliverability) Old school HTML format    I'm running out of ideas and I'm starting to be in the hot seat and I am very fearful for my job position.   If you can offer any wise words i will be very grateful. Thank you in advance.


In C++, what is "^" symbol means? except XOR

I read an article about C++ language. There is lines using "^", not XOR. Sample code is like:  array<String^>^args = System::Environment::GetCommandLineArgs();


How to agree with a negative statement: with "yes" or with "no"?

This question here asks about answering negative questions:      I have a completely different question. I want to know:   how do we agree or disagree with negative statements in English.   Example:  ––This is not a duplicate question.  ––Yes, it is a new one.  or  ––This is not a duplicate question.  ––No, it is a new one.


Tikz cuts off top of text in tikzpicture

I am drawing an arrow with text above it  \documentclass[tikz]{standalone}  \usetikzlibrary{decorations.text} \begin{document} \begin{tikzpicture} \draw[<-, thick, postaction={decorate, decoration={text along path,text align=center, raise=.7em, text={Process}}}]         (0, 0) to [bend left=60] (5, 0); \end{tikzpicture} \end{document}   The result cuts off the top of the text of the label.    How can I fix the bounding box of the tikzpicture so that it adjusts itself the text of the label? Can I get the decorations to extend the bounding box, the way arrows.meta does for arrows?    I would like the bounding box of the tikzpicture to adjust automatically to the contents of the picture, rather than have to fine tune a fixed value.   If I put the text in its own node, it doesn't get cut off, but then it doesn't follow the path of the arrow.   Of course, I can not raise the text, but then it is too close to the arrow.     The accepted answer  has nothing to do with my problem, since the arrows.meta package doesn't change the bounding box for decorations. The other answers to that question suggest adding margins, but I do not want to have to fine tune the margin parameter (and then have to change it again, if I move the arrow decoration).


Expansion of space or contracting of matter?

Can the expansion of the Universe effect be explained by contraction of the overall matter instead? That is, all material objects are in fact contracting, due to what the universal space seems (and only seems) to be expanding. Are there any theoretical arguments or experimental data that preclude replacement of the universal space expansion by the universal matter contraction as an explanation tool of the nature of the very process?


Mth position of the Nth Ordered permutation of an ordrered set all elements taken at once

Since there is no ordering in sets I am not sure what would one call a set that is strictly ordered, aka an array in programming e.g. $S={a_1,a_2,\cdots,a_n}$ where $a_k< a_{k+1}$ the first ordered permutation will be $[a_1,a_2,\cdots,a_n]$ the second will be $[a_2,a_1,\cdots,a_n]$ and so on  Is there a non recursive formula to calculate the Mth position of the Nth Ordered permutation? so that one will be able to calculate all the elements of the Nth entry without having to calculate all the ordered permutations before it? For the above two example Let $P[N,M,S]$ be the Mth position in the Nth ordered permutaion of S then $P[1,1,S] = a_1,\quad P[1,2,S] = a_2,\quad P[1,n,S] = a_n$  $P[2,1,S] = a_2,\quad P[2,2,S] = a_1,\quad P[2,3,S] = a_3,\quad P[2,n,S] = a_n$


C - initialization of pointers, asterisk position

What is the most proper way to place asterisk? Why?  1)    type*     var; 2)    type      *var;


Why didn't the Resistance use Y wing bombers to assault SKB in The Force Awakens?

Why didn't the Resistance assaulting Starkiller Base use Y wing bombers?   It seems silly to me to conduct a bombing run or assault on a hard target without using craft designed specifically for bombing.  It is at least mentioned in passing that the Republic may be quietly funding them, so why did they not employ Y wings?


My question is how to be the most annoying possible to someone trying to do a sql injection, I probably did not really express right what i was trying to do and looking for in what I wrote blow.    Thanks to everyone for your help in advance. I am trying to learn MySQL.  I was going to set up a database to practice with but I was on here reading and looking for examples, and kept seeing people saying they where going to get an SQL injection.   I have been reading about this for a while now, and I'm getting more confused the more I read. I have decided to go with PDO to prevent this. Even though from what I read it's the prepared statements that makes it safe, and I will still have to whitelist it.    My question is if someone can give beginners like myself a set up we can use that will be pretty effective at stopping these attacks. From what I understand it seems almost impossible to stop them, I saw someone say something about the dns is the only sure way. I would like to learn to do this the right way even though I probably don't need too much security right now.   If I'm not wrong, they can still use blind injections even if you use PDO.  If so, I was thinking of adding a delay of 2-5 seconds or something like that. I don't know if that would be too much on the user end, I'm just learning, and have no real world experience.   Also the type of things I will be doing, will probably be very basic for now... mom & pop type stuff. If I build someone a site with a user name and password I don't want them to get these attacks, I just don't like it. So if it is a little slow but more secure I would like to be at least able to give them that option.  My thinking is to be really annoying to them and hopefully not be worth it.   From what I read also the length of the table names or user names can make it harder for them, say using phrases instead of just 6-8 letters.   Also I think least privilege will help as well, but there seems there is always a way around everything, and if you're new and don't know exactly what your doing, you're going to be vulnerable.   I have copied code from somewhere that I was going to adapt for my needs, but I really have not tried to put together what I'm looking for yet, still in the reading and learning phase.   <?php   require_once "dBug!.php";  $dsn = "mysql:host="; $user_name = ""; $pass_word = "";  $connect = new PDO($dsn, $user_name, $pass_word);  $sql = "SELECT * FROM books WHERE id <= 10";     $result = $connect->prepare($sql);  $status = $result->execute();   if (($status) && ($result->rowCount() > 0)) { $results = array();   while ($row = $result->fetch(PDO::FETCH_ASSOC)) {     $results[] = $row; }   new dBug($results);  }  $connect = null;   ?>


The spelling of number is number, but the abbreviation is No (№). There is no letter o in number, so where does this spelling come from?


How to add a description to an enumerated math equation in line? When I do this the sentence is printed without word spacing\item$\lim_{x\to\infty}\frac{c}{x^n}=0, where c is any constant and n > 0$ and it prints like  How to make proper word spacing for sentence inserted?


Sub-10K users can't unfollow deleted posts from "Followed posts" tab

A  was raised on MSE:  I am still seeing notifications of edits on a post I followed, which was deleted:   at  states that:  Going forward, you should be able to unfollow deleted posts from both the question page itself and from the "Following" tab on your user profile.  But right now, neither the followed and deleted post nor the "Unfollow" button are showing up in my Followed posts tab.  Those with the  privilege will not be bothered by this problem, owing to the fact that they can see deleted posts, but those of us who don't have that privilege can't. As the ability to unfollow deleted posts from the Following tab existed before, assuming the quote above is accurate, could we reinstate that ability?  UPDATE The  this question was duplicated to is now marked , but I am still unable to unfollow a deleted post from my "Followed Posts" tab, so I'd like this to be reopened.  See  at the duplicate for more details.


how to prove that every cauchy sequence is a convergent sequence in $\mathbb{R}$

I just want to know how can I prove that:  Let $\{x_n\}\subset\mathbb{R}$ a real numbers sequence, if $\{x_n\}$ is a cauchy sequence, then $$x_n\longrightarrow x\in\mathbb{R}$$


Name for a word whose sound is contrary to its meaning

As onomatopoeia means words that sound like what they mean, is there a word which means words that sound contrary to what they mean?  Pulchritude is an example of such a word.


How many cables are you allowed to run through a single hole in a wooden floor joist? For example, could I run five 12-2 cables through a 1-1/8" hole? I know they physically fit, but is there a code to regulate this? Is there any limit on this or some table for guidance?


How to pass variables and methods as command line arguments in python

I have a scenario. I have to pass the parameter values to the methods in script and methods to execute. Example: File name app.py value1 = sys.argv[1] value2 = sys.argv[2] def method1():     print(value1)  def method2():     print(value2)  Command I am trying to execute: python3 app.py 10 12 method2 In the above the output should be method2() print value is 12


I accidentally opened a trojan on windows XP. How to proceed?

I don't really need to remove it. It's ok if it just doesn't open anymore. Is there a program to remove all unwanted autoruns from registry ?


Let $p$ and $q$ be positive numbers having a sum of $1.$ What is the minimum value of $(p+(1/p))^2 + (q+(1/q))^2?$

Options are:  A. $20$ B. $12$ C. $12.5$ D. $13.3$  And steps to  calculate would be appreciated.  Edit: Apologies for having repeated the same question here.


At work , i would prefer to set my phone in such a way that only the calls from my family group will ring , while all other contact calls should be silent. And later i should be able to switch it back to normal.  In general , there are sound profiles for phones, but the profiles are not specific to a contact or a group, i need a work profile which will set Family - Normal Others - Silent . etc  Is there any app in the market that would help me with this??


What does "Processing triggers" actually mean?

Pretty much the title. I've seen it so many times and never really thought until today on what it actually does. A quick google search pulled up nothing in relation to it. An explanation would be much appreciated to get this out of my mind!


Feature given by class is already given by race. What to do RAW?

I have a player in my game with an Aasimar Warlock with a Celestial Patron. At 6th level, Celestial Patron grants "... resistance to radiant damage, and when you cast a spell that deals radiant or fire damage, you add your Charisma modifier to one radiant or fire damage roll of that spell against one of its targets." Aasimar race also grants radiant damage resistance. Is there a rule (RAW) that tells what to do in cases like this?


Wifi hotspot software package other than ap-hotspot?

I have tried using ap-hotspot to create a wifi-hotspot but it gives me some problem every time I use it . I just want to ask is there any other software  package that create a wifi-hotspot othen than ap-hotspot ?


I use dell Inspiron 5520 laptop with latest BIOS version A13 with 4GB RAM and Intel core i5 processor.  Recently I have removed Windows 8 and installed Ubuntu 12.04 by disabling the UEFI mode. Since installing Ubuntu I found my laptop overheating. Help me regarding this issue  !! i use AMD Radeon graphic card


Hi. What does ex- muslim Pakistani mean gramatically?

Does it mean neither a muslim nor a pakistani anymore? Or it means muslim and ex pakistani. I will be very thankfull if you people kindly elaborate this for me.


It is a consequence of a theorem known as Krull’s Hauptidealsatz that   every non-unit element in a Noetherian domain is contained in a prime   ideal of height 1.   Assuming this, prove that a Noetherian domain R is a UFD if every prime ideal of height 1 in R is principal.   I want to use the following characterization of UFDs:   ACCP holds every irreducible element is prime   The first point is obvious since R is noetherian, but I couldn't prove the second. I do not know whether the way I try is correct or not. Please help me, thank you.


Biggest advantage to using ASP.Net MVC vs web forms

What are some of the advantages of using one over the other?


So here is the problem      Solve $$4^x + 6^x = 9^x$$ for $x$.   I am trying to find its real solution.  I was trying in this way!! $$6^x\left( \frac {4^x}{6^x} + 1\right) = 9^x$$ $$\left({\frac 23}\right)^x +1=\left({\frac 32}\right)^x$$ but I'm stuck . . . Will anyone help ?


I was wondering if the 'Home' button is still a must on a website menu, or are users already used to clicking on the Logo?  There is a qustion on ux.stackexchange.com about this topic -  but it is around 2 years old, and I'm curious if user expectations have changed? Because:   more and more sites do not have a 'Home' button even huge sites like Facebook, Apple, Microsoft, Android, HP do not use 'Home' button and there are some sites who use a  instead of a Home button    So I suppose most internet users learned that they have to click on the Logo to return to the Home site, but haven't seen any up-to-date study about this topic.


Is it possible to recover data after a hard drive has been reformatted and windows reinstalled on the drive? As a friend has forgot to back up some important word documents.


Universal rope if for every continuous function $f:[0,1] \rightarrow \mathbb{R}$ with $f(0)=f(1)$

A number $a \in \mathbb{R}$ is an "universal chord" if for every continuous function $f:[0,1] \rightarrow \mathbb{R}$ with $f(0)=f(1)$ exists $x,y \in [0,1]$ with $|x-y|=a$ and $f(x)=f(y)$. Determine all universal ropes.


Is it possible to get a diagonal subset symbol?

I'm asking if I can get the subset symbol, or any symbol really for that matter if possible, for LaTeX, namely the subset symbol would have symmetry about the line y=x. If you know what I mean.


Why is my camera metering indoor scenes as darker than I expect, forcing me to use a high ISO?

I am shooting in natural light, with my subject facing a full floor-to-ceiling south facing window. You would think my meter would allow ISO between 200-400 in bright light, but I was lucky to get it to 640, with f/3.2 and 1/60 (manual mode).  I've read other places that people say put your ISO down to 100 for indoor shots for greatest clarity (especially sharp eyes) — but don't know how I can with subjects potentially moving. Is there a setting in my camera (Canon 5D Mark III) I am missing, or something that might be making my meter need more light?


What is the reason behind the multiple Spider-Man reboots?

Spider-Man is the one franchise that is on course to a third reboot in a span of 15 years.   My question is what was the reason for these numerous reboots of Spider-Man which pretty much follow the same origin story for the Marvel superhero.  Has the comic creator or studio ever spoken out about the reasoning behind the same?


What's the difference between For and To?

Here's an example I'm trouble in.        English is important for me.   English is important to me.      Can anybody tell me which one to use? If it depends on adjective, will you teach me it?


I would like to mimic the use of Alfred on Mac OS X, where if you try to open an app after searching for it, it will only open a new window if the program is not already running, otherwise it will set the focus on the currently running instance of that application. Is there anyway to change the default behavior of the launcher to check for this before opening a new window?


How can I force 5.1 output over HDMI on my Geforce 660 in Windows 8?

I have my computer's Geforce 660 connected via HDMI to my TV, which is connected via optical out to a 5.1 soundbar + surrounds. I can force my PS3 to output 5.1, and this is passed through to the soundbar successfully. However, on my Windows 8 machine, I believe the drivers communicate with the TV which reports only 2 channel capability (possibly because of its internal speakers) so that's what my computer sends it.  I can't find a way for the TV to report 5.1 capability to my computer, so instead I'd like to force 5.1 out of my video card. It seems like there are ways to do this on previous versions of Windows by installing special drivers but I can't find anything for Windows 8.  Here's the screen where I was hoping to see 5.1:


uninstall software center applications via bash

Trying to uninstall an old version of Eclipse running:  sudo apt-get remove eclipse   I'm told the program isn't installed but I can see it in the software-center and run the program.  When I try to uninstall the program via software-center it looks like it's about to work but always fails. It seems like a password prompt is supposed to pop up but isn't for some reason. (Note: running i3-wm likely related)  Is there a way I can just uninstall the old version of eclipse via terminal?


I'm trying to create a directory which has space in name e.g. "user test" when I fire mkdir -p "user test" it works for me.  When I put "user test" in variable mkdir fails, it creates "user and test" separately  var="user test" mkdir -p $var    I also tried mkdir -p "$var"  Can someone please suggest where I'm doing wrong ?


How can I format a special section title?

I want to make my section titles look like the ones in this figure. However I have no idea what font that is, or how to only change the font for the tiles and sections etc. or how to get the fancy box. Is there a way to figure this out? Any pointer or direct solution is appreciated.


I am trying to create a 2 dimensional int array of size 800. This is my code: #include <iostream> int main() {     int array[800][800];     std::cout << 1; }  My problem is that it never prints 1. I am using g++ as my compiler so it might have something to do with it's inner workings. Furthermore, I couldn't find anywhere on the web saying there was a limit (except for 2^32 and such) to the size of a c-style array. When I try creating one with size 700 it works just fine. Does anyone have an idea where this limit comes into effect and how I can overcome it?


echo lines of file - but no more than N characters per line

I would like to print the tail of a file (could be also head or cat in general) to the screen but restrict the number of characters per line.  So if a file contains ...  abcdefg abcd abcde abcdefgh   ... and the maximum number is 5, then the following should be printed:  abcde abcd abcde abcde   How would I do that?


Markdown application for mac ox ? github compatible?

I am looking for a markdown editor for mac os x. There seems to be so many around.  Ideally one that is compatible with github MD  Anybody can recommend one that allows preview, and with really good functionality and kept up to date and frequent updates.  Its not important if its pay or free..  Thanks in advance  The question being presented as a duplicate, is out of date, the program they suggest hasn't been updated for a while.


How to preserve tabs in Vim when you paste something?

When I paste any code into Vim, I the following happens.    How could I tell Vim not to screw up my tabs?


Edit:  This question is actually a duplicate of . It's solution worked for me.    Basically, I want to do what  is doing, but using bibtex instead of biblatex.   To summarize what it's doing there, I want a single .bib files to store the bibliography entries for an entire document. When I run a section file (ie. not the main.tex), it cannot find the Sources.bib and so fails to make the reference. If I run main.tex though, the reference that is inside the section file resolves perfectly fine.  For a minimum working example (it doesn't run correctly, but it gives you the idea), see below.  So I have the following file structure:  project_dir |    main.tex |    background.tex |    Sources.bib   Inside main.tex, I have:  %%%% main.tex %%% \documentclass[10pt]{ClemsonThesis} \usepackage{amsmath} \usepackage{subfiles}  \begin{document} % blah blah blah  \subfile{background.tex}  \bibliographystyle{plain} \bibliography{Sources} \end{document}     %%% background.tex %%% \documentclass[main.tex]{subfiles}  \begin{document}  %blah blah blah Here's some random text I have in a few paragraphs. Here's a citation for referencing an external resource: \cite{McCormack2012}.  \end{document}     %%% Sources.bib %%% @Inbook{McCormack2012, author="McCormack, Percival", title="The Vortex", bookTitle="Vortex, Molecular Spin and Nanovorticity: An Introduction", year="2012", publisher="Springer New York", address="New York, NY", pages="1--65", abstract="The first notable works on fluid motions appeared in the early seventeenth century. Descartes in his ``Principia Philosophiae'' (1644) considered that space was filled with frictional vortices, so that the planets are carried along by the vortex motions. Vortices had fascinated mankind for many centuries before Descartes. It was considered that life had started in the water of the primeval vortex -- in whirlwinds and whirlpools.", isbn="978-1-4614-0257-2", doi="10.1007/978-1-4614-0257-2_1", url="https://doi.org/10.1007/978-1-4614-0257-2_1" }   Using the files below, if I compile background.tex, the bibtex reference fails. If I run main.tex, the bibtex reference that is in background.tex resolves perfectly fine.  I've tried adding \bibliography{Sources} to the end of the background.tex file, but got nothing.


Is it acceptable to use "is become" instead of "has become"?

In the King James version of the Bible there is a verse like this:     The Lord is my strength, and my fortress, and my song. And He is become my salvation.   Is it still feasible to use "is become" instead of "has become" and what is the semantic difference?


WiFi range dropped in Windows 7 and Windows 10

I had Windows 10, then 1 day my wifi range dropped. It shows only one signal when I'm on the same floor of the router, and no signal found when even go out of the door. For many other reasons (and for this one too) I switch from Windows 10 to Windows 7. But the problem is same. I tried to update the drivers but nothing happened.  It also sometimes shows Limited Access and a yellow triangle on network indicator, but all the other devices connected via that network (wired AWA wireless) showing Internet Access and also fine range. So it may not be the problem of the router. I can't even open the router page (192.168.0.1) when Limited Access shown. So I think It's not the internet, but the router is not connected to my system.  Here's my WIFIcard: Realtek RTL8723BE 802.11 bgn Wifi Adapter  What I do is troubleshoot the problem and after waiting 10-18 seconds my internet came back.   Is it my system's hardware problem or something else? Can I resolve this thing?


Deleting my account only for one site and not for all sites

Previously I asked to delete only my Meta account, but my Stack Overflow account was deleted as well. How can I prevent this in the future?


I created 12 partitions from July 2017 through July 2018 and didn't leave an empty partition at the end. Hence, am having a hard time adding new partitions using the split function. I even tried switching the oldest partition to a staging table but "split range" is taking a very long time to execute. The goal of this project was to reuse the old partitions by archiving oldest partition to another table but I am not able to use the switch function as it's taking a very long time.  Please advise so I can fix this issue. Here are the scripts:  CREATE PARTITION FUNCTION APITPartFunc AS RANGE LEFT FOR VALUES (     '2018-01-31T00:00:00'     ,N'2018-02-28T00:00:00'     ,N'2018-03-31T00:00:00'     ,N'2018-04-30T00:00:00'     ,N'2018-05-31T00:00:00'     ,N'2018-06-30T00:00:00'     ,N'2018-07-31T00:00:00'     ,N'2018-08-31T00:00:00'     ,N'2018-09-30T00:00:00'     ,N'2018-10-31T00:00:00'     ,N'2018-11-30T00:00:00'     ,N'2018-12-31T00:00:00'     )  CREATE PARTITION SCHEME [APITScheme] AS PARTITION [APITPartFunc] TO (     [ApiTPartitions]     ,[ApiTPartitions]     ,[ApiTPartitions]     ,[ApiTPartitions]     ,[ApiTPartitions]     ,[ApiTPartitions]     ,[ApiTPartitions]     ,[ApiTPartitions]     ,[ApiTPartitions]     ,[ApiTPartitions]     ,[ApiTPartitions]     ,[ApiTPartitions]     ,[ApiTPartitions]     )      CREATE TABLE [dbo].[test] (     [id] [bigint] IDENTITY(1, 1) NOT NULL     ,[user_id] [uniqueidentifier] NOT NULL     ,[client_id] [smallint] NOT NULL     ,[api_tracking_type_id] [smallint] NOT NULL     ,[dt] [datetime] NOT NULL     ,[event_data] VARCHAR NULL     ,[entity_id] VARCHAR NULL     ) ON [APITPartScheme] (dt) GO  ALTER TABLE [dbo].[test] ADD CONSTRAINT [PK_test_id_dt] PRIMARY KEY CLUSTERED (     [id] ASC     ,[dt]     )     WITH (             PAD_INDEX = OFF             ,STATISTICS_NORECOMPUTE = OFF             ,IGNORE_DUP_KEY = OFF             ,ALLOW_ROW_LOCKS = ON             ,ALLOW_PAGE_LOCKS = ON             ) ON APITPartScheme  --I was trying to add an empty partition by  ALTER TABLE test switch PARTITION 13 TO teststaging PARTITION 13  ALTER PARTITION scheme apitpartscheme NEXT used apitpart13  ALTER PARTITION FUNCTION apitpartfunction () spit range ('2018-08-04')  ALTER TABLE teststaging switch PARTITION 13 TO test PARTITION 13 --this would be after split works but the above script took forever so I stopped it.


boolean[] vs. BitSet: Which is more efficient?

What is more efficient in terms of memory and CPU usage — an array of booleans or a BitSet? Specific BitSet methods are not used, only get/set/clear (==, =, Arrays.fill respectively for an array).


Can Weights and Offset lead to similar results in poisson regression?

In  in paragraph 1.83 it is stated that:   "In the particular case of a Poisson multiplicative GLM it can be shown that modelling claim counts with an offset term equal to the log of the exposure produced identical results to modelling claim frequencies with prior weights set to be equal to the exposure of each observation."  I am not able to find any further references of this results, so i took upon some empirical testing in which i was not able to find proof that the statement is correct. Can anyone provide some insight in why this results may be right/wrong.   FYI, i used the following R code to test the hypothesis, in which i could not obtain similar results for the two mentioned cases:  n=1000 m=10  # Generate random data X = matrix(data = rnorm(n*m)+1, ncol = m, nrow = n)  intercept = 2 coefs = runif(m) offset = runif(n) ## DGP: exp of Intercept + linear combination X variables + log(offset) mu = exp(intercept + X%*%coefs + log(offset)) y = rpois(n=n, lambda=mu)  df = data.frame('y'=y, 'X'=X, 'offset' = offset) formula = paste("y ~",paste(colnames(df)[grepl("X", colnames(df))], collapse = "+"))  #First model using log(offset) as offset fit1  = glm(formula, family = "poisson", df, offset = log(offset)) #Second model using offset as weights for individual observations fit2 = glm(formula, family = "poisson", df, weights = offset)  #Third model using poisson model on y/offset as reference dfNew = df dfNew$y = dfNew$y/offset fit3 = glm(formula, family = "poisson", dfNew)  #Combine coefficients with the true coefficients rbind(fit1$coefficients, fit2$coefficients, fit3$coefficients, c(intercept,coefs))   The coefficient estimates resulting from running this code is given below:   >       (Intercept)       X.1       X.2       X.3        X.4       X.5       X.6 [1,]    1.998277 0.2923091 0.4586666 0.1802960 0.11688860 0.7997154 0.4786655 [2,]    1.588620 0.2708272 0.4540180 0.1901753 0.07284985 0.7928951 0.5100480 [3,]    1.983903 0.2942196 0.4593369 0.1782187 0.11846876 0.8018315 0.4807802 [4,]    2.000000 0.2909240 0.4576965 0.1807591 0.11658183 0.8005451 0.4780123               X.7       X.8       X.9      X.10 [1,]  0.005772078 0.9154808 0.9078758 0.3512824 [2,] -0.003705015 0.9117014 0.9063845 0.4155601 [3,]  0.007595660 0.9181014 0.9076908 0.3505173 [4,]  0.005881960 0.9150350 0.9084375 0.3511749 >    and we can observe the coefficients are not identical.


I need to make use of an array of unsigned bytes. I need to send certain characters over the network to a server and some of these characters are greater that 127.   I have a simplified version of the code below to try and understand the concept:  int i= 160; byte j = (byte) i; System.out.println((byte)i); System.out.println(j);   and this gives an output of: -96 -96  I need to print 160. As the server is expecting a byte of 160 and if it receives -96 it does not accept the value. The reason I used an int is that when I was reading how to get around the problem, I often came across the suggestion to just use an int, but I don't quite understand that, as I need my array to be of type byte.  This is the part of my code where I send the array:  public boolean send(byte[] data) {     try {      out.write(data); // Write the data to the outStream      out.flush();     } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); return false; // Return false if the TCP Transmit failed  // } return false; }   I would really appreciate it if some one could help me.


How to draw a shape like this using TikZ?


Python: Ctrl+Click for buttons (capture invocation event)

Is it possible to get if Ctrl key is pressed when I click on my python button?  I would like make different behaviors for my button operator.  Example: LMB - Select some objects CtrlLMB - Deselect some objects  I don't use a modal operator / the modal() method. I've been making a simple script.


how to show that when an edge is removed from K5, the resluting subgraph is planar.

this question might be simple to others, but I'm stuck on this question. "prove that when I deleted an edge from $K5$, it has planar sub-graph .  So, I know that G is planar if and only if G contains no sub-division of $K5$ or $K3,3$. So that means when I delete an edge from K5, I no loger have sub-division of K5 and therefore, the subgraph is planar. But how do I show that explicitly that when I remove edge from $K5$, it will have planar subgraph? (I think this question is somewhat related to Kuratowski's theorem)


Is it wrong to define functions on ordinals?

After familiarizing myself with the ordinal numbers and their arithmetic, I’ve been (perhaps sloppily) using function notation to refer to certain combinations of arithmetic operations on ordinals. For example, letting $$f(x)=x^2+\omega x$$ Gives values like $$f(\omega + 1) = \omega^2 + \omega$$ However, I recently realized that it might be mathematically incorrect to define a function on all ordinals. Because if asked to state the domain and codomain of this function, I would have to say “the set of all ordinals”... which isn’t a set, it’s a class. And as far as I know, functions can’t be defined on classes, only sets. Question: Is it wrong to define functions that accept any ordinal as an argument? (By “wrong”, I mean - does it lead to contradiction or paradox?)