Hint for proving $|f'(0)|\leq \frac{1}{2}\max_{z,w\in \overline{D}(0,1)}|f(z)-f(w)|$

What I have done so far:  Since $f$ is holomorphic on $U$ and   $\overline{D}(0,1)$, we have by   cauchy's integral formula we have   \begin{align*}     f'(0)=\frac{1}{2\pi i}\int_{\partial D(0,1)}\frac{f(w)}{w^2}dw   \end{align*}   So we have   \begin{align*}     |f'(0)|&=|\frac{1}{2\pi i}\int_{\partial D(0,1)}\frac{f(w)}{w^2}dw|\\     &\leq \frac{1}{2\pi}\int_{\partial D(0,1)}|\frac{f(w)}{w^2}dw|, \;     \text{by the triangle and the modulus of $i$ being 1}\\     &\leq \frac{1}{2\pi}\max_{z,w\in \overline{D}(0,1)}\frac{f(w)-f(z)}{(w-z)^2}     ||\partial D(0,1)||=\frac{1}{2\pi}     \max_{z,w\in \overline{D}(0,1)}\frac{f(w)-f(z)}{(w-z)^2}     2\pi\\     &=\max_{z,w\in \overline{D}(0,1)}\frac{f(w)-f(z)}{(w-z)^2}   \end{align*}  Of course by continuity the difference quotient can't blow up, but I am concerned this isn't the best way to approach the problem. I also have not used compactness of the closed disc, although that may be just to justify taking the max rather than the sup of f in the statement.


What happens if I modify the Merkle–Damgård hash method?

Does the Merkle–Damgård hash function still offer Collision Resistance (CR) when the following changes are made? Each case is independent from the other.  Here is what I want to modify:   Say I want to get rid of the IV at the beginning and replace it with the first block of the message ($M_1$). That is, $T_0 = M_1$ and the 2nd tag $T_1$ will be generated using the compression function $h$, so that $T_1 = h(M_1,M_1)$. Instead of what it should have been: $T_1 = h(IV,M_1)$. Instead of using IV as the first tag $T_0$ and adding the message length in the last block, set $T_0$ to be the the message length $q$ (such that it is padded to the block length). Instead of outputting the result of Merkle–Damgård $H(m) = h(T[i-1]; M[i])$ we just output $T[i-1] || M[i]$, where $||$ denotes concatenation. Assuming in this version of Merkle–Damgård, the last block will just be the length of the message.   Can someone tell me if any of this cases offers Collision Resistance? Please explain why this is the case.


I have two functions:  def centify(amount_nbr):     if amount_nbr:         try:             amount_nbr = int(float(amount_nbr) * 100)         except ValueError:             amount_nbr = 0     else:         amount_nbr = 0     return amount_nbr  def uncentify(amount_nbr):     if amount_nbr:         amount_nbr /= 100.     else:         amount_nbr = 0     return amount_nbr   When I test a load of floats:  for i in range(0, 100):     i *= 0.01     if i != uncentify(centify(i)):         print "%f - %f" % (uncentify(centify(i)), i)   It returns that the rounding is wrong for:  0.280000 - 0.290000 0.350000 - 0.350000 0.410000 - 0.410000 0.470000 - 0.470000 0.570000 - 0.570000 0.570000 - 0.580000 0.690000 - 0.690000 0.700000 - 0.700000 0.820000 - 0.820000 0.830000 - 0.830000 0.940000 - 0.940000 0.950000 - 0.950000   What is going on? And how do I make them the exact inverse?    I need to fix the fact that:  num = 316805.79 print centify(num)   returns 31680578 rather than 31680579


How do you compute the DC operating point (IC,VCE) and draw an AC equivalent circuit?

I just started learning about electronics and decided to quickly sketch a circuit. When it comes to OP and changing the said circuit into an Ac equivalent, I got stuck. Sorry in advance if this is considered a basic question.


Why is it correct to assume $f = e^{\lambda x}$ in differential equation?

I was solving the following differential equation: $$f'' + f = 0$$ And, as I learned in class, I assumed that $f = e^{\lambda x}$ and then found the roots of the polynomial and found the solution. But then the following came to my mind: Why is it correct to assume that $f = e^{\lambda x}$? How do we know that by doing this we are indeed finding all the solutions of the equation and we aren't only finding the solutions that take that form? Because doing this looks like a guessing game, we try to guess the solution and then find it by correcting and fixing the values of $\lambda$.


Is it possible to replicate spawn conditions for wither skeletons?

As most probably know, in terraria, it is possible to replicate certain spawn conditions artificially in controlled conditions. One example is the meteorite in which having x amount of meteorite ore, meteor heads will spawn. Similarly in minecraft, Iron Golems can be farmed for iron if one were to artifically create a village large enough for them to spawn.  That said, in minecraft, it is stated in the wiki that wither skeletons spawn in nether fortresses. Is it possible to replicate the condition for wither skeletons to spawn just like one would do in terraria or perhaps like the Village Iron Golem farm?


unable to mount ntfs partition created inside widows 10

If i try to open any of partition, I get error message in a box.  Error mounting /dev/sda8 at /media/viratraaz/Documents: Command-line `mount -t "ntfs" -o "uhelper=udisks2,nodev,nosuid,uid=1000,gid=1000,dmask=0077,fmask=0177" "/dev/sda8" "/media/viratraaz/Documents"' exited with non-zero exit status 14: The disk contains an unclean file system (0, 0). Metadata kept in Windows cache, refused to mount. Failed to mount '/dev/sda8': Operation not permitted The NTFS partition is in an unsafe state. Please resume and shutdown Windows fully (no hibernation or fast restarting), or mount the volume read-only with the 'ro' mount option.


Is there any physical or mental cost to casting spells?

Often in fantasies involving magic casting spells requires a certain physical or mental toll on the caster. I don't recall any mention of spells being physically or mentally taxing in the Harry Potter universe.  Does this mean they can cast an unlimited number of spells in a given day without any negative effect to themselves?


Profile is still counting a hidden community that no longer exists

I had a profile on a private beta site a while back that I listed under my Hidden Communities so it wouldn't show up on my profile on other sites. The private beta was closed, but my profile is still showing that I have 1 hidden community, both on :    ...and on :    But by going to /users/hidecommunities/[me] I can see that there isn't actually anything hidden anymore:     (By instinct I want to blame caching, but it's been several months.)


AllureRestAssured , how to ignore logging headers

I am using rest-assured and allureRestAssured for testing api given().header("Content-Type", "application/json")                 .header("key", key()).filter(new AllureRestAssured())                 .body(body.toString())                 .post(baseURI);  Problem here is its logged headers also , which contains auth key , which I dont want to be exposed in report generated , how can I ignore that .


SSH keys should be generated with email or without email?

Tried to google for this basic query related to SSH key generation, but didn't get expected answer  ,   explains to create key without email  Other links explain to create with email     What's the good practice ? Should I use email or avoid it ?


How to interpret regression coefficients in a log-log model

I'm using a linear model to analyse some data,       y~N(mu, sigma) where      mu[y] <- Intercept + Beta1X + Beta2X1 + Beta3X2     and Beta2 = Beta1^2 Beta[n] ~ N(mu.b[n], sigma.b[n])   but I have had to log-transform both the predicted and all the predictor variables, because I'm using BUGS, just for efficiency. Gelman alludes to this being called "elasticity" and says the coefficients can be directly interpreted as " a Beta% increase in X is associated with a 1% increase in y".  However, my  results :                Estimate Std. Error t value Pr(>|t|)     (Intercept)  0.1135924  0.1495142   0.760    0.448     B1           1.4934436  0.0580981  25.706   <2e-16 *** I(B1^2)     -0.1477196  0.0062205 -23.747   <2e-16 *** B2           0.0003612  0.0515368   0.007    0.994   suggest that there is a 150% increase in y, with each 1% increase in Beta1 which would be bonkers. Also, how do interpret the "non-linear" or self-interaction term? My suggestion is : A 15% decrease in the effect of B1 on y occurs with each 1% increase in Beta1.  However If I don't transform either the predicted or the predictors I get:  Coefficients:               Estimate Std. Error t value Pr(>|t|)     (Intercept)  5.382e+01  3.410e+00  15.782  < 2e-16 *** B1          -3.026e-02  8.775e-03  -3.449 0.000591 *** I(B1^2)      8.654e-06  7.828e-06   1.106 0.269264     B2           2.363e+00  2.490e+00   0.949 0.342789   In which the effect of X1 seems to be reversed, and the effect sizes are miniscule ( certainly not in the order of 150%  and 15% respectively)  Hoping for correction!!  Thanks


I installed kubuntu-desktop using sudo apt-get install kubuntu-desktop but I no longer want to use KDE.  How do I remove all the packages that were installed by this command ?  Thank you


I have an Android device that supports both 2.4 and 5Ghz bands. Also my WiFi router is dual band. I know that 5GHz band supports higher speeds but the difference isn't significant for my connection speed (50 Mbps). Does connecting to the 5GHz drain more battery than 2.4 GHz?


What is this square chat bubble / balloon icon on the top left of a screen. It has a call out arrow on bottom left

There is a square chat balloon icon or chat bubble appearing on the notification panel on the top left of screen. What does that indicate ? It has a call out arrow on the bottom left.


How to solve the problems in "sudo apt-get update"

is my /etc/apt/source.list file. I get many problems in the output of sudo apt-get update:  $ sudo apt-get update [sudo] password for tim:  Err http://cran.cnr.Berkeley.edu precise/ Release.gpg                             Could not connect to cran.cnr.Berkeley.edu:80 (169.229.201.201). - connect (111: Connection refused) Err http://ppa.launchpad.net precise/main Sources           404  Not Found Err http://ppa.launchpad.net precise/main i386 Packages     404  Not Found  W: Failed to fetch http://cran.cnr.Berkeley.edu/bin/linux/ubuntu/precise/Release.gpg  Could not connect to cran.cnr.Berkeley.edu:80 (169.229.201.201). - connect (111: Connection refused)  W: Failed to fetch http://ppa.launchpad.net/venerix/blug/ubuntu/dists/precise/main/source/Sources  404  Not Found  W: Failed to fetch http://ppa.launchpad.net/venerix/blug/ubuntu/dists/precise/main/binary-i386/Packages  404  Not Found  W: Some index files failed to download. They have been ignored, or old ones used instead.   I have several errors at the end of the output. How can I solve the problems?  Thanks!


How can I shrink a Logical Volume, and re-allocate the freed space into a new partition on the same drive?

I have a drive, sda. It has two partitions:  sda1: /boot sda2: LVM managed in Volume Group volgrp01   volgrp01 contains the following Logical Volumes:  lv_root (30 GB) lv_swap (8 GB) lv_scratch (430 GB)   What I want to do is reduce lv_scratch to 50 GB, and re-allocate that newly freed 380 GB into a new partition, sda3 (which I'll then add to another Volume Group).  I've attached an image of my desired BEFORE and AFTER. I'm right in the middle of learning about LVM, and while I can grasp the idea of resizing Logical Volumes within a Volume Group, I'm unsure of how one would re-allocate that space into a new partition.  I'm using RHEL6.


There's a sentence: I think I must do it before he has finished / he will have finished his project.  What's correct?  Or maybe does it need another tense?


In one of my wordpress theme function, this code is being used to calculate total billable amount: ceil(($cost * (1 + ($charges / 100))) * 100);  There is a little miscalculation happening for below scenario.  Scenario:  $charges = 9; $cost = 100;  echo ceil(($cost * (1 + ($charges / 100))) * 100);   The above code outputs 10901 whereas it should be 10900.  It works fine for other scenarios like:  $charges = 4; $cost = 90.7;  echo ceil(($cost * (1 + ($charges / 100))) * 100);  //outputs 9433, which is fine because manual calculation results 9432.8   Question:   Why is that happening? How can I prevent that? Any alternate function to round to next nearest integer? (only if amount is floating value)


Let $A\subseteq \Bbb R$, A is an infinite set of positive numbers.  Suppose, $\exists k \in  \Bbb Z$ for all finite $B\subseteq A$.  $\sum_{b\in B}b<k$  Prove $A$ is countable.   I have a hint: $A_n=\lbrace a \in A | a>\frac1n\rbrace$  I understand that $B \in \Bbb Q$ and $k$ can be the last element of $A$ but I'm not really sure if that's right or what to do with it.  Any help would be appreciated.


VLC suddenly stopped working, this is what I get now when I try to run it:  main libvlc: Running vlc with the default interface. Use 'cvlc' to use vlc without interface. main interface error: option qt-volume-complete does not exist skins2 interface error: no suitable dialogs provider found (hint: compile the qt4 plugin, and make sure it is loaded properly) skins2 interface error: cannot instantiate qt4 dialogs provider   I tried reinstalling multiple times, and there is no other program using the qt4 libraries. Also, the command line interface doesn't appear to do anything. When I try to "force" the qt4 interface, I get:  main interface error: no suitable interface module main libvlc error: interface "default" initialization failed   ldconfig -p | grep libQt:  libQtXmlPatterns.so.4 (libc6,hard-float) => /usr/lib/arm-linux-gnueabihf/libQtXmlPatterns.so.4 libQtXml.so.4 (libc6,hard-float) => /usr/lib/arm-linux-gnueabihf/libQtXml.so.4 libQtSql.so.4 (libc6,hard-float) => /usr/lib/arm-linux-gnueabihf/libQtSql.so.4 libQtScript.so.4 (libc6,hard-float) => /usr/lib/arm-linux-gnueabihf/libQtScript.so.4 libQtNetwork.so.4 (libc6,hard-float) => /usr/lib/arm-linux-gnueabihf/libQtNetwork.so.4 libQtGui.so.4 (libc6,hard-float) => /usr/lib/arm-linux-gnueabihf/libQtGui.so.4 libQtDeclarative.so.4 (libc6,hard-float) => /usr/lib/arm-linux-gnueabihf/libQtDeclarative.so.4 libQtDBus.so.4 (libc6,hard-float) => /usr/lib/arm-linux-gnueabihf/libQtDBus.so.4 libQtCore.so.4 (libc6,hard-float) => /usr/lib/arm-linux-gnueabihf/libQtCore.so.4 libQtCLucene.so.4 (libc6,hard-float) => /usr/lib/arm-linux-gnueabihf/libQtCLucene.so.4


Why is it that $$  \left(1+\frac{1}{n}\right)^n < \left(1+\frac{1}{m}\right)^{m+1}, $$ for any natural numbers $m, n$?   I have tried expanding using the binomial series and splitting into cases. I understand why it is trivially true when $m=n$ but I am not sure if there is a rigorous proof for other cases?


When I try to access the local variable jimFound outside of the block it was declared in the first Java code piece I get a compilation error    Error:(10, 13) java: cannot find symbol,  symbol:   variable jimFound,  location: class Scope  Which is what I expected.    public class Scope {      public void main(String args[]){         String name = "Jim";         if (name.equals("Jim")) {             boolean jimFound = true;         }         if(jimFound) {             System.out.println("I found Jim!");         }     } }   When I try the same with Python my program manages to find Jim.  name = "Jim" if name == "Jim":     jim_found = True if jim_found:     print "I found Jim!"   The console result is "I found Jim!"  Why is this happening?


"I saw one of my classmates who was/were?"

Which one is correct? Please explain.  I saw one of my classmates who was also on the boat while travelling to Saint Martin.   I saw one of my classmates who were also on the boat while travelling to Saint Martin.  In this sentence what is the subject and why? How can I find the subject in sentences like this?


I understand the answer to this question is that it entirely depends on the data set.  However, this does not help people understand if their model is suitable or whether they should explore other variables.  So I am attempting to getting this question answered by people with experience in different fields where statistics is applied.   Assuming the model was not overfit and no other problems existed with the model, what I would like to know from someone experienced is the vastly different projects they worked on from very different industries and R^2 they obtained from their models so that people may gain a 'feel' whether they are heading in the right direction.  This question is of a highly atypical format so let me know if this is inappropriate for this website and I will remove it. Any suggestions on where to post this will also be appreciated.


I've heard that "me neither" is incorrect. Instead one should say "neither do I." People definitely say "me neither" conversationally, but is it technically incorrect?


Is there any relation between the rank and the number of zero eigenvalues?


Story about food designers who create cultured meat, eventually cultured human flesh

I'm looking for a short story I read probably 30 years ago.  The two main characters in the story were food designers who specialized in cultured meat grown from cells cloned from unlikely sources. They seemed almost like a cross between geneticists and fashion designers, producing new, interesting meats that would become trendy. I seem to recall that one of their hits was steak-sized meat cultured from lark's tongue cells.   At the end of the story they're presenting their latest creation, offering tastes but without saying what it is. The taster loves it. The twist, of course, is that it's cultured human flesh, a steak made from cells cloned from one of the main characters.  The ending might be a bit predictable but this was the first time I had heard of some of the ideas, and as a kid it was kind of mind blowing.


Axis/vector notation in Minkowski diagrams

Learning special relativity and working with Minkowski diagrams for a while now i am still trying to get my head around some oddity.   From my understanding time can often be seen as the dependent variable in those diagrams, so why put it to the vertical axis? What confuses me even more is the apparent convention to denote a point in space time $(t,x)$ even though $x$ is on the horizontal and $t$ is on the vertical axis, so the usual notation would be to refer to that vector as $(x, t)$.  Are there mostly historical reasons or why is it beneficial to use this notation and to violate usual conventions?


I have a question about an argument used in Schwabl's "Advanced Quantum Mechanics" concerning the properties of the Klein-Gordan-Equation (see page 120):    Since the eigenenergies of free solutions are $E= \pm \sqrt{p^2c^2+m^2c^4}$the energy states aren't bounded from below. But I don't understand why that  then K-G-equation provide a scalar theory that does not contain spin and then could only describe particles with zero spin.   Intuitively, I guess because that spin can't regard by a scalar equation but I find this "argument" too squishy and would like to know a more plausible argument.


What was the point of Tom Riddle's diary resurrecting a 16-year-old instance of Voldemort?

As we know, the intention behind Voldemort's Horcruxes was to anchor his soul to meaningful and rare artifacts and leave them in hard-to-reach places, defended by things like Inferi, the Gringotts defenses, or deadly curses. His spirit remains on the mortal plane when his physical body is destroyed, until every single Horcrux is destroyed, which would therefore have to be prevented at all costs.  The diary doesn't seem to fit this pattern. It was a plain, relatively random object, which wasn't guarded by anything at all. Sure, you might argue, but it was his first-ever Horcrux- yet he definitely could've retrieved or moved it to a secure location later on.   Instead, the diary was left carelessly unguarded, eventually entrusted to Lucius Malfoy in a plot which would have eventually resulted in creating a 16-year-old corporeal Tom Riddle out of the soul part enclosed within it.  But what's the point?  During the events of CoS, there already exists a 67-year-old wraith-like part of Tom Riddle a.k.a. Lord Voldemort, which was wandering around somewhere abroad. On top of that, there is absolutely no way Dumbledore wouldn't recognize this young Tom, considering the fact that he kept a close watch on Tom during his time at Hogwarts.  As we know that a Horcrux contains only the memories and personality of the person at the time it was created, this 16-year-old Tom Riddle can;t contain anything that is not already within the mind of the 67-year-old Tom Riddle Wraith Spirit.  If Tom Riddle's diary had managed to recreate his 16-year-old self by draining Ginny's life-force completely, what would this have achieved? How would this help the existing instance of Tom Riddle in any way?


While I know that $$\sum_{n=1}^{\infty} \frac{1}{n^2} = \frac{\pi^{2}}{6}$$  But trying to evaluate this has left me stumped $$\sum_{n=1}^{\infty} \frac{1}{n^2+1}$$  I evaluated it through wolfram alpha, it gave me $\frac{1}{2}(\pi\coth(\pi)-1)$.  What would be a good way to start evaluating this series?


If $p \equiv 1 \pmod{N!}$ prove there are no primitive roots $\pmod p$, $g$, that are less than $N$

I've recently been looking at different questions and proofs in my book and one eludes me for the 2nd day in the row.     Let $N \geq 4$. Show that if $p$ is a prime such that $p \equiv 1 \pmod{N!}$ then none of the numbers $1, 2, \ldots, N$ are primitive roots modulo $p$.   I've tried using CRT, the fact that $\left(\frac{ab}{p}\right) = \left(\frac{a}{p}\right)\left(\frac{b}{p}\right)$ and Gaussian sum $G(p)$ properties, yet to no avail.  This proof has been really bugging me, could you please point me in the right direction?


Sorry about this dumb question, but i´ve recently found out that you can declare a String or string variable at C#. I would like to know the difference between them, which one is used at specific situations, etc. Thanks for the help and for your time.


How to download and install Utorrent for Ubuntu 14.04

I have no idea what I'm doing when it comes to this. I downloaded the .tar.gz file from the Utorrent website and extracted it to a folder I made in the Home directory. I tried executing the executable file but nothing seemed to happen.


I am going over Durret's probability textbook and one of the proofs uses the inequality  $$\sum_{k=n+1}^\infty \frac{1}{k^2\log k} \leq \frac{1}{n\log n}$$  But, as with much of the textbook, gives no explanation. I was thinking you could take one of the $k$'s out front to and then integrate $1/k\log k$ but that doesn't seem to be of much help.  How can I show this to be true (rather than just take Durret's word for it)?


Only 923 MB out of 4 GB RAM showing on Windows 10 HP laptop

I have Windows 10 32-bit installed on my laptop () with a single 4 GB stick of RAM. But the system only reports 932 MB of memory. I have tried removing the module and putting it back.  Output of wmic memorychip list full:  BankLabel=BANK 1 Capacity=4294967296  DataWidth=64  Description=Physical Memory  DeviceLocator=Bottom-Slot 2(under) FormFactor=12 HotSwappable=  InstallDate=  InterleaveDataDepth=1  InterleavePosition=2  Manufacturer=A-DATA Technology  MemoryType=24  Model= Name=Physical Memory  OtherIdentifyingInfo=  PartNumber=AM1U16BC4P2-B19H PositionInRow=1 PoweredOn=  Removable= Replaceable=  SerialNumber=00004EB9  SKU=  Speed=1333 Status=  Tag=Physical Memory 1  TotalWidth=64  TypeDetail=128 Version=    This question is different from the marked duplicate because there are 3 out of 4 GB missing!


How to make subdomain in my domain from my web like slack?

How to make subdomain in my domain from my web like slack does, example my main domain mydomain.com and from my website create subdomains *.mydomain.com


What is a neat way to evaluate a Python function with different parameter combinations?

I'm having a function that I want to evaluate with different parameter combinations, e.g.  params1 = [1, 6, 100] params2 = [True, False] params3 = ["blue", "red", "green"]   Here is my straight forward attempt to do this:  res = np.zeros((len(params1), len(params2), len(params3)))  for i1, p1 in enumerate(params1):     for i2, p2 in enumerate(params2):         for i3, p3 in enumerate(params3):             res[i1, i2, i3] = myfunc(p1,p2,p3)   This works, but adapting it to more complex scenarios is not only cumbersome but more importantly makes the code messy and thus increases the chance of mistakes.  My next approach to handle this in a more structured way would be to write a recursive function that would starts one for loop in one parameter and then inside this loop call itself.  But since my problem seems like a quite general problem, I wonder if there is a better (e.g. more basic or neat) way to address this.  EDIT: Thanks for the helpful comments. It was suggested to use for params in itertools.product(params1, params2, params3): myfunc(*params).  Unfortunately does not do the trick for me, since I also need the indices. I edited my code, since this crucial part was missing.  I should also give more background on what I want to use this for, since this seems like a standard problem to me and there might be completely different approaches: I want to evaluate the numeric output of myfunc in some part of it's high dimensional parameter space, to later explore it and in particular look for maxima and minima under constraints (e.g. minima for parameter2 = True). Therefor my approach was to evaluate it in that part of the space and store the result in the numpy array res.  Again, thanks a lot for any suggestions.


Error on Implementing custom List View with BaseAdapter

I need help I have been trying to find a way on how to implement custom list view and I am getting an error:-     java.lang.NullPointerException: Attempt to invoke virtual method 'void   android.widget.TextView.setText(java.lang.CharSequence)' on a null   object reference at   com.edis.edis.HospitalAdaptor.getView(HospitalAdaptor.java:62)   The following is the Object that I have created and it's called Data.java.  public class Data {  private double lat, lon; public String name; String groupA, groupB, groupAB,groupO; public int url_image;   public Data(double lat, double lon, int url_image, String name, String groupA, String groupB, String groupAB, String groupO) {     this.lat =lat;     this.lon = lon;     this.url_image =url_image;     this.name = name;     this.groupA =groupA;     this.groupB =groupB;     this.groupAB = groupAB;     this.groupO = groupO;  }  }   Then I have created an Adapter where I get an error (null object) on the line where is chakula.setText((hospital.name)).  The following is the adapter I have used BaseAdaptor. HospitalsAdaptors.java      public class HospitalAdaptor extends BaseAdapter{     Context context;     List<Data> datas;       public HospitalAdaptor(Context context, List<Data> datas) {          this.context = context;         this.datas = datas;      }       @Override     public int getCount() {         return datas.size();     }      @Override     public Object getItem(int position) {         return datas.get(position);     }      @Override     public long getItemId(int position) {         return position;     }       @Override     public View getView(int position, View convertView, ViewGroup parent) {         Data hospital = (Data)getItem(position);          if(convertView == null){               convertView = LayoutInflater.from(context).inflate(R.layout.fragment_hospitals,parent,false);             //convertView = LayoutInflater.inflate(R.layout.fragment_hospitals,parent,false);         }          TextView chakula = (TextView)convertView.findViewById(R.id.hospitals_name);         ImageView pilau = (ImageView)convertView.findViewById(R.id.hospitals_image);          chakula.setText(hospital.name);          Glide                 .with(context)                 .load(hospital.url_image)                 .centerCrop()                 .crossFade()                 .into(pilau);          return convertView;     } }


Has a SHA256 output ever been found consisting entirely of the same character?

Is it possible to have an output consisting purely of one character and does this change the entropy of that output? (If that's even possible to ascertain.)  As an example, the Bitcoin cryptocurrency is slowly and inadvertently compiling a list of inputs which produce outputs with successively larger numbers of trailing zeros in its blockchain. Will these ever be used to study the SHA-256 algorithm?


Stuck in login loop after partial upgrading

I'm on Ubuntu 20.04. The Software Updater prompted to do a partial upgrade and I proceeded. Then after the reboot I'm stuck on a login loop. Edit: Update and Upgrade don't work either in the command line interface.


Why is $X^4 + \overline{2}$ irreducible in $\mathbb{F}_{125}[X]$?

I want to prove that $f = X^4 + \overline{2}$ is irreducible in $\mathbb{F}_{125}[X]$.  I know that $\mathbb{F}_{125}$ is the splitting field of $X^{125} - X$ over $\mathbb{F}_5$, and that this is a field extension of $\mathbb{F}_5$ of degree 3, and that $\mathbb{F}_{125} = \mathbb{F}_5[X]/(g)$ where $g = X^3 + X - \overline{1}$.  If we put $\alpha = X + (g)$ then $\{\overline{1}, \alpha, \alpha^2\}$ is a basis for $\mathbb{F}_{125}$ considered as a vector space over $\mathbb{F}_5$. Hence every element $x \in \mathbb{F}_{125}$ can be written $x = a_0 + a_1\alpha + a_2\alpha^2$, with $a_i \in \mathbb{F}_5$.  How do I proceed?


Modern science has given clear evidence that smoking can lead to many diseases.   in this sentence，“that smoking can lead to many diseases” is an Appositive clause,but I wonder if I can say      Modern science has given clear evidence where（in which） smoking can lead to many diseases.   what is the difference between them？ please help me，thank you.


What would be your recommendation for the text which could be useful for someone starting with lattice theory? Suggestion for both books and online materials/lecture notes are welcome.    This was asked as a part of  and I did not like that it was combination of two different questions. (One of them on geometric modular lattices and the other one about text recommendation.)  I don't expect the user to post a follow-up question, since he was not seen at MSE for some time. I think that this could be a useful for some users here, so I've decided to post it myself.


Looking for a (short?) story about a cryo ship looking for habitable planets

I read this story/novella at least 15 years ago, probably 20 or more. It is about a ship, travelling through the universe, looking for habitable planets. Why, I can't remember. People are held in Cryo Stasis and I think they are wearing nothing in the chamber but some kind of mesh. Every time the ship gets close to a planet it wakes one or two of the people (one woman, one man?) to check it out but they never find anything good. I think in the end they wake up and discover, that they have arrived back at Earth. Other details are very vague but I seem to recall there was lots of stuff about a (blue?) light, dreaming/dreams and something about the cold, or cold blue lights or similar. Does that ring a bell for anyone?


Layout bug on desktop web: spacing and alignment of the Next Privilege popup's Learn More button

Steps to reproduce:  Log in. Go to your profile for any SE site (not your network profile) Click on the "next privilege" progress bar.  What's wrong:  The text showing your numeric progress is right up against the Learn More button, with no space between. There is also no space above the button.   I think that, in the past, the Learn More button was right-aligned in the popup. I tried float: right; margin-top: 0.3em; in my web inspector, and that seemed to fix the issue:  I'm obviously not suggesting that SE folks just copypasta my solution and ship it. Just trying to do as much of the work as I can. I tried on Meta and SO; I see it in both places, so I don't think it's site-specific nor dependent on which badge you're tracking. Chrome 84 and Safari 13.1.2 both show the issue. I don't imagine this part is relevant, but in the interest of thoroughness, I'm using a 2018 15" Macbook Pro running Catalina 10.15.6. EDIT: I agree that this is a duplicate of the linked question, but mine and the linked questions are, IMO, not duplicates of the one that one is linked to. Related, but not duplicates. Close mine, but reopen that one?


I saw the following  that provides which should actually be a false proof since $0^0$ is not defined to be $1$.     $(a+b)^{n}=\sum_{k=0}^{n}\binom n{ k}a^kb^{n-k}$.   Put $a=0, b=1, n=0$. This gives $1^0=\binom0{0}1^00^0\implies 0^0=1$.   Also the person claiming this to be true says that:  "Also, $0^0$ is the number of mappings from the empty set to the empty set. Surely there’s no other answer to this number of mappings than $1$. Any arguments against setting $0^0=1$ are based on limiting forms $f(x)^{g(x)}$ where, as $x$ approaches some number, $f(x)$ and $g(x)$ approach zero but $f(x)^{g(x)}$ does not approach $1$. That doesn’t matter one bit: the limit of $⌊x⌋$ as $x$ tends to $0$ does not exist, but everyone is happy with defining $⌊0⌋=0$ all the same."  Why is this claim true if it is and why otherwise? What is the possible discrepancy in this proof and defining $0^0$ as $1$? Why is it beneficial to define it so?


This is a relatively large project, but I'll try to put all necessary things here.   /**  Removes the record with Key k from the dictionary. It throws a      DictionaryException if the record is not in the dictionary. */  public void remove(Key k) throws DictionaryException{          deleteNode = findNode(k);         if (deleteNode == null) throw new DictionaryException("Error: Record doesn't exist in the dictionary!");         else{             //check if children are leafs             if(deleteNode.getLeftChild() == null || deleteNode.getRightChild() == null)                 //set it to itself                 replace = deleteNode;             else                 //otherwise replace with successorNode                 replace = successorNode(deleteNode);             //store left child if it exists             if (replace.getLeftChild() != null)                 child = replace.getLeftChild();             //else, store right             else                 child = replace.getRightChild();             //check if both nodes are null             if (child != null)                  child.setParent(replace.getParent());             //else replace the node that needs to be deleted             else{                 //replace left child of parent                 if(replace == replace.getParent().getLeftChild())                      replace.getParent().setLeftChild(child);                 //else replace right                 else                     replace.getParent().setRightChild(child);             }                //store information of the replacing node, within the deleteNode             if (replace != deleteNode)                  deleteNode.setRoot(replace.getRecord());         }     }   This method has an null-pointer error on the parent stuff. I'm not sure how to go about dealing with it.  This is an Ordered Dictionary stored in a BST. Nodes consist of Records which consist of (Key,data) where Key is (name,type). Essentially a Record is ((name,type),data).  I can provide more information if necessary. I've been stuck here for a quite while any help is appreciated!


can I upgrade my 32bit windows 8.1 os to 64bit Windows 10 with a bootable 64bit Win 10 disk? or without paying again for 64 bit os?

I've my windows 8.1 os and it's 32 bit. Recently I wanted to try 64 bit programs and I want to upgrade my os to win 10. Can I upgrade my win 8.1 to Win 10 ? With windows 10 64bit boot able disk without going through normal update from os? by selecting the upgrade option in insall options in bootable cd? Without doing clean win 10 64 bit OS installation. i don't want to pay for 64 bit os again.


If $f$ is continuous then there exists $x\in [0,1]: f(x)=x$

I wish to prove the following by contradiction:     Let $f:[0,1]\rightarrow[0,1]$ be a continuous function. Prove that there exists $x\in [0,1]$ such that $f(x)=x$.   Proving this directly, one would have to define a new function $g(x):=f(x)-x$ and prove that there exists $x\in [0,1]$ such that $g(x)=0$ using Intermediate Value Theorem, hence $f(x)=x$. But I'm struggling to elaborate a proof by contradiction.  My approach is as follows. Suppose by contradiction that it does not exist $x\in [0,1]$ such that $f(x)=x$. Then for all $x\in [0,1]$, $f(x)\neq x$. Then $f(x)>x$ or $f(x)<x$ for all $x$. This is where I'm not sure if it's correct.  If $f(x)>x$ for all $x\in [0,1]$, let $x:=1$. Then $f(1)>1 \implies f(1)\notin [0,1]$ which is a contradiction because $f$ was defined in $[0,1]$  If $f(x)<x$ for all $x\in [0,1]$, let $x:=0$. Then $f(0)<0 \implies f(0)\notin [0,1]$ leading to the same contradiction as above.  I'm skeptical because my contradiction does not involve $f$s continuity. Is the proof correct? If not, how can I approach this by contradiction? Thanks.


Is it bad math style to use one letter for indexing two objects?

Is $$\sum_{i\in I_1} a_i + \sum_{i \in I_2} b_i$$ or $$\prod_{i\in I_1} a_i \cdot \prod_{i \in I_2} b_i$$ confusing or bad math? Should I rather use $j$ for indexing the $b$'s?


Problem with showing that every Contractive Sequence is Cauchy

Here's the proof which shows that every contractive sequence satisfies the Cauchy criterion, and I don't seem to be convinced with it.    My doubts:   Why is the fact that the RHS tends to zero on approaching larger $n$, sufficient to say that we can always find a natural number (say $K$) such that the Cauchy criterion is met for $m,n \ge K$ What exactly is the epsilon we choose, here? Is it the expression on the RHS? If so, we should be able to show that the RHS ranges over all real numbers, because we're concerned with all $\varepsilon >0$


Want to extend a PHP class from two classes one of which is abstract

Can I extend a PHP class from two classes, one of which is abstract and other one is not? like:  class customer extends SomeControllerClass implements SomeAbstractClass { ... }   the reason to do is that I have my commonly used functions and logic in the abstract class.


The degree and minimal polynomial over $\mathbb{Q}$ of $j\sqrt{2}$

What is the degree and minimal polynomial over $\mathbb{Q}$ of $j\sqrt{2}$, where $j$ denotes $-\frac12+\frac{\sqrt3}2i$, a primitive thrid root of unity? I see that $(j\sqrt{2})^6=8$.  Then $P(j\sqrt{2})=0$ with $P=X^6-8$. Can we say that $P$  is irreducible polynomial over $\mathbb{Q}$?


class made with toggleClass() doesn't alert on click event

Another toggleClass() problem. There are dozens question about this jQuery function but I could not find this specific one.  I have 2 buttons. One toggles the class of the other on click. This works fine since the colour changes, however when I use a click() event on the 'new' class nothing happens.  html  <button type='button' id='button1'>button 1</button> <button type='button' id='button2'>button 2</button>   css  .pushed {     background-color: salmon; }   js  $('#button1').click(function () {   $('#button2').toggleClass('pushed'); });  $('.pushed').click(function () {   alert('pushed!') });   you can try it here:


Expected Value of the number of letters we need to draw from the alphabet

We draw letters (a-z) independently and uniformly at random from the alphabet with replacement. If we draw a collection of letters, then we say that we can write a word when the collections contains all the letters needed to spell the word. For example, if we draw ‘a’, ‘c’ and ‘t’, then this collection writes the word ‘cat’, but also ‘act’, ‘at’ and ‘a’.   Let $N$ be the random variable that denotes the number of letters we needed to draw before we can write ‘rowel’ for the first time. Find $E[N]$ and $\text{Var}[N]$.  Could someone help me by showing me how to approach this question?


How can I make a list with most used commands in terminal?  I know that this question may be unuseful for any future proposals for some of us, but even like this, the list can be useful when we don't remember a command used once or some times in the past, when we can search at the end of this list.


Picking post numbers reveals titles of deleted questions

If you change the post number in any question URL to a number of a deleted question, you will be redirected to a 404 page, but the URL in your address bar will change to contain the title of the deleted question.  Example URL, try it in private browsing mode:   Works with "q" and "a" links too, but not "posts" links.  This works while logged in, but the fact that it also works while logged out, in my opinion, is much worse.


Windows Server 2012 R2 and Visual Studio 2015 Community

So I'm trying to install Visual Studio 2015 Community on my Windows Server 2012 R2 box which will end up being a Jenkins build server. Attempting to do so gives an error saying that I need to install KB 2919355.    So I attempt to download the right KB from the . The two files that I would assume to work are either Windows8.1-KB2919355-x64.msu and Windows8.1-KB2919355-x86.msu (just to try) and neither update work, saying that the update is not applicable.    I've not been able to get this working and I haven't been able to find a proper way to fix this. Can anyone offer any suggestions or solutions? Thanks!


So, I have a question that says for any group elements $a$ and $x$, prove that $|xax^{-1}| =|a|$, where $|\cdot|$ is the order of an element.  I know that $xx^{-1} = e$ and $ae=a$, but I'm not sure how to get the $x$'s on the same side.   Currently, for my proof, which is not much, I have:  Let $n = |xax^{-1}|$, then $(xax^{-1})^n = e$.  Honestly, I have no idea where to go from here, or if what I've got is even right. I would really appreciate just a point in the right direction.


Installing Ubuntu 14.04 LTS on Dell Inspiron 5537 leads to low graphics mode error

I am trying to install Ubuntu 14.04 on Dell Inspiron 5537, and the installation completes with no errors, but when I boot into Ubuntu I get a popup window saying:      the system is running in low-graphics mode ... device settings could not detected correctly.   This model iscertified by Canonical! When I choose re-configure, I keep getting the same window! When I press esc, I get a black screen, and nothing happens.  How can I fix it?


In Java, what are the performance and resource implications of using  System.currentTimeMillis()    vs.   new Date()    vs.   Calendar.getInstance().getTime()   As I understand it, System.currentTimeMillis() is the most efficient. However, in most applications, that long value would need to be converted to a Date or some similar object to do anything meaningful to humans.


Getting a physics PhD from Cambridge with self funding?

I will probably not be able to secure any funding. I can self fund the costs, but I heard that this is looked down upon and most advisors would not want to spend time with me as I am inferior to others who have gotten funding which will hurt the quality of my research and publications. Is this true? Will self funding my PhD make it harder for me to find advisors and will I be looked down upon/ produce worse publications? I know that similar questions exist, but I am mainly asking if advisors will be less willingly to become my advisors if I am self funded (do they think students who got funding have more potential than those that did not refuse funding)?


How to use 2013 iMac as second monitor with Windows 10 PC

I have a late 2013 iMac with Thunderbolt port (no mini display port) that I want to use as a second monitor for a new PC running Windows 10.  I have parallels on the iMac but no Miracast so don't seem to be able to use Target Display Mode.  Are there any cables/adapters I can use to connect the two?  Thanks.


Cheapest way to wire or withdraw money from US account while living in Europe

I'm currently living overseas in Europe.  I work as a consultant for a US based company which pays me US dollars deposited to my US bank account.  It's getting to be pretty expensive when I withdraw money from the ATM (around $25 USD), or if I wire money from the US bank (Bank of America) to my account here ($45 USD).  Anyone have any suggestions on how to transfer money from my US account by paying less fees?  Any bank that has better deals, any services I can use, like online services?


I have difficulty in understanding the axiomatic approach of set theory and i decided to study logic.After seeing some lectures on set theory my doubt grown up like a beast.  So please  suggest me some good books in logic and in set theory which will help me understand what the concepts are.ALSO SUGGEST ME SOME GOOD VIDEO LECTURES IF AVAILABLE.  Thanks in advance.


Multivariate linear regression vs. several univariate regression models

In the univariate regression settings, we try to model   $$y = X\beta +noise$$  where $y \in \mathbb{R}^n$ a vector of $n$ observations and $X \in \mathbb{R}^{n \times m}$ the design matrix with $m$ predictors. The solution is $\beta_0 = (X^TX)^{-1}Xy$.  In the multivariate regression settings, we try to model   $$Y = X\beta +noise$$  where $y \in \mathbb{R}^{n \times p}$ is a matrix of $n$ observations and $p$ different latent variables. The solution is $\beta_0 = (X^TX)^{-1}XY$.  My question is how is that different than performing $p$ different univariate linear regression? I read  that in the latter case we take into consideration correlation between the dependent variables, but I don't see it from the math.


Mathematically rigorous books on special and general relativity

I am looking to study physics as a mathematician. I am interested in books on special and/or general relativity, written in a style of rigor that would be acceptable to a mathematician. I would like a large number of examples of such books.


MacBook Pro 13" 2015 A1502 recording vinyls through headphone jack

My 2013 MacBook Pro allowed me to convert audio from old cassette tapes and vinyl to digital by using a 3.5mm Male To Male Stereo Audio Cable from the player's headphone jack into the headphone jack of the MacBook Pro 2013.  In the System Preferences, you could change the headphone jack to function as input rather than output.  Easy. You could use Quicktime to record and other apps.  I found some old vinyl albums that I want to convert to digital but my 2015 MacBook Pro does not seem to be able to do what I mentioned above.  Playing the music  over the air and recording using the internal microphone would not be acceptable.    Suggestions to accomplish this?


My client has dual monitors which they use to display two different websites in a public space. They want to be able to hard reboot the system and have it automatically start two browser windows, one on each monitor, and go to the appropriate websites.  We can get the browsers to start easily enough using the startup folder, but have not been able to figure out how to get one browser window to go to one screen, and the other window to the other screen automatically. Is there a way of doing this in powershell, or some other scripting language?  We are running Windows with IE, but also have Firefox installed.


interpreting interaction between two categorical variables in OLS


Morphisms that permit arbitrary lifts/extensions.

In any category, monic/epic morphisms are equivalently characterized as the morphisms that map to injective maps under the co-/contravariant Hom-functors. Now I'm interested in the morphisms that map to surjective maps, i.e. that permit extensions/lifts of any morphisms along them. I will call them $\overline{\text{monic}}/\overline{\text{epic}}$ in the following.  I'd like to know if these concepts already have an established name, and if there is some theory around them: Maybe there is some criterion to determine if some morphism is $\overline{\text{monic}}/\overline{\text{epic}}$ analogous to the usual (co)kernel pair criterion for monic/epic morphisms. Are there other types of $\overline{\text{monic}}/\overline{\text{epic}}$ morphisms, as there are effective/regular/strict/strong/extremal mono- and epimorphisms?


Taylor series for exp(exp(x)) using just the power series for exp(x)

I'm trying to figure out how to calculate the power series for exp(exp(x)) using exp(x) and then to write down the first few terms. I have the answer for the terms but I don't know how they arrived at it   Thanks in advance  For the first few terms we have: exp(exp(x)) = e(1 + x + x^2 + . . .)


Can I made vimrc config valid for some type of files and invalid for others?

I'm a python programer. And I added these two line in my vimrc:  highlight ExtraWhitespace ctermbg=grey guibg=grey match ExtraWhitespace /\s\+$/   which will highlight the redundant spaces at the end of line with grey.  But recently I'm starting to write md docs. It's soft break requires two spaces at the end of line.  Thus my vimrc config makes these md docs less readable in editing stage.  Is there a way that some vimrc config can working selectively only for some kind of file, or be forbiddened when editing a particular kind of file?


I can't install any app from Ubuntu software in 18.04

When I try to install app from Ubuntu software it shows below error  after running following command i found this error sanny@sanny-Inspiron-14-3467:~$ sudo apt-get update --fix-missing Hit:1 http://ppa.launchpad.net/daniruiz/flat-remix/ubuntu bionic InRelease Hit:2 http://ppa.launchpad.net/noobslab/icons/ubuntu bionic InRelease           Hit:3 http://archive.ubuntu.com/ubuntu bionic InRelease                         Hit:4 http://ppa.launchpad.net/papirus/papirus/ubuntu bionic InRelease        Reading package lists... Done W: Target Sources (main/source/Sources) is configured multiple times in /etc/apt/sources.list.d/noobslab-ubuntu-icons-bionic.list:2 and /etc/apt/sources.list.d/noobslab-ubuntu-icons-bionic.list:3 W: Target Sources (main/source/Sources) is configured multiple times in /etc/apt/sources.list.d/noobslab-ubuntu-icons-bionic.list:2 and /etc/apt/sources.list.d/noobslab-ubuntu-icons-bionic.list:3 sanny@sanny-Inspiron-14-3467:~$ sudo apt-get -f install Reading package lists... Done Building dependency tree        Reading state information... Done The following packages were automatically installed and are no longer required:   libllvm7 libllvm8 Use 'sudo apt autoremove' to remove them. 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded. 1 not fully installed or removed. After this operation, 0 B of additional disk space will be used. Setting up flat-remix-gnome (20191117) ... /var/lib/dpkg/info/flat-remix-gnome.postinst: 4: /var/lib/dpkg/info/flat-remix-gnome.postinst: make: not found dpkg: error processing package flat-remix-gnome (--configure):  installed flat-remix-gnome package post-installation script subprocess returned error exit status 127 Errors were encountered while processing:  flat-remix-gnome E: Sub-process /usr/bin/dpkg returned an error code (1) sanny@sanny-Inspiron-14-3467:~$ sudo apt autoremove Reading package lists... Done Building dependency tree        Reading state information... Done The following packages will be REMOVED:   linux-headers-5.3.0-26 linux-headers-5.3.0-26-generic   linux-image-5.3.0-26-generic linux-modules-5.3.0-26-generic   linux-modules-extra-5.3.0-26-generic 0 upgraded, 0 newly installed, 5 to remove and 0 not upgraded. 1 not fully installed or removed. After this operation, 344 MB disk space will be freed. Do you want to continue? [Y/n] y (Reading database ... 545443 files and directories currently installed.) Removing linux-headers-5.3.0-26-generic (5.3.0-26.28~18.04.1) ... Removing linux-headers-5.3.0-26 (5.3.0-26.28~18.04.1) ... Removing linux-modules-extra-5.3.0-26-generic (5.3.0-26.28~18.04.1) ... Removing linux-image-5.3.0-26-generic (5.3.0-26.28~18.04.1) ... /etc/kernel/postrm.d/initramfs-tools: update-initramfs: Deleting /boot/initrd.img-5.3.0-26-generic /etc/kernel/postrm.d/zz-update-grub: Sourcing file `/etc/default/grub' Generating grub configuration file ... Found linux image: /boot/vmlinuz-5.3.0-61-generic Found initrd image: /boot/initrd.img-5.3.0-61-generic Found linux image: /boot/vmlinuz-5.3.0-51-generic Found initrd image: /boot/initrd.img-5.3.0-51-generic Found Windows Boot Manager on /dev/sda2@/EFI/Microsoft/Boot/bootmgfw.efi Adding boot menu entry for EFI firmware configuration done Removing linux-modules-5.3.0-26-generic (5.3.0-26.28~18.04.1) ... Setting up flat-remix-gnome (20191117) ... /var/lib/dpkg/info/flat-remix-gnome.postinst: 4: /var/lib/dpkg/info/flat-remix-gnome.postinst: make: not found dpkg: error processing package flat-remix-gnome (--configure):  installed flat-remix-gnome package post-installation script subprocess returned error exit status 127 Errors were encountered while processing:  flat-remix-gnome E: Sub-process /usr/bin/dpkg returned an error code (1)


I studied basic field theory from J.A. Gallian in U.G. and Fraleigh. and a year ago I self studied it from Galois Theory by David A. Cox, and I got pretty good at it. But in last year I was mainly studying groups and non-commutative ring theory, so now I feel like I have lost my sharpness in Field theory and now I want to reread whole Galois field theory. But doing Cox again will feel boring so I was thinking to switch to a  new book. After googling a lot I have shortlisted these small and interesting book-  1) Fields and Galois theory by Howie 2) Galois Theory by Rotman 3) Field and Galois theory by Morandi 4) Galois Theory by Escofier  Which one of these texts is most interesting and insighting? Which one should I buy first, e copies of all of them looked great, but which one I should purchase and read first.  If there are any other suggestions, you are welcome!


While studying Ramanujan's Collected Papers I came across a paper titled "Some Definite Integrals" which appeared in Messenger of Mathematics, ${\tt XLIV}, 1915, \mbox{10-18}$. It contains lot of weird integrals for which Ramanujan has given proofs.  However in one instance he discusses about the integral \begin{align} &\int_{0}^{\infty}\frac{dx}{\left(1 + x^{2}\right)\left(1 + r^{2}x^{2}\right)\left(1 + r^{4}x^{2}\right)\cdots} \\[5mm] = &\ \frac{\pi}{2\left(1 + r + r^{3} + r^{6} + r^{10} + \cdots\right)}\label{1}\tag{1} \end{align} where $0 < r < 1$.  Ramanujan derives this formula from \begin{align} &\int_{0}^{\infty}\frac{\left(1 + arx\right)\left(1 + ar^{2}x\right)\cdots}{\left(1 + x\right)\left(1 + rx\right)\left(1 + r^{2}x\right)\cdots}x^{n - 1}\,\mathrm{d}x \\[5mm] = &\ \frac{\pi}{\sin\left(n\pi\right)} \prod_{m = 1}^{\infty}\frac{\left(1 - r^{m - n}\,\,\right)\left(1 - ar^{m}\,\right)}{\left(1 - r^{m}\,\right)\left(1 - ar^{m - n}\,\,\right)}\label{2}\tag{2} \end{align} where $0 < r < 1, n > 0, 0 < a < r^{n - 1}$ and $n$ is not an integer and $a$ is not of the form $a = r^{p}$ where $p$ is a positive integer.  Unfortunately, Ramanujan does not prove the formula (\ref{2}).   Is there any direct approach to establish (\ref{1}) without using (\ref{2}) or some way to establish (\ref{2}) $?$.


What content to put on parent page when it exists only for the subpages

On tree structure website there's always the problem of what contents to put in the parent page, you know, the page that exists only as a point to subpages to attach.    Write some general descriptive text of what to expect on the sub pages?  Write "click menu on the left"? Generate/duplicate submenu on the page content area? Leave completely empty? Something else?   And of course there is the functionality of skipping the parent page altogether, just automatically jump to the first subpage.  Number one has been my preferred choice, but no solution seem free of problems.  Is there a patented solution to this problem that I have missed?


Getting a string variable value from another controller javafx

i have two controllers a login and main, when logincontroller validates a user then maincontroller holds the control, i tried this method, but not working, the userName variable gives null value.  logincontroller class:  public class loginController implements Initializable{      private String user;     public String getUser() {         return user;     }    if((user.equals(loginUsername.getText()) && (pwd.equals(loginPassword.getText())))){             switch(role){                  case "Admin": Stage adminStage=new Stage();           FXMLLoader adminLoader = new FXMLLoader(getClass().getResource("/FXML/Admin/Admin.fxml"));           Parent adminRoot = adminLoader.load();           AdminController adminController = (AdminController)adminLoader.getController();           adminController.setLoginController(this); }   maincontroller class:  public class AdminController implements Initializable {     @FXML     private Label userName;      public void setLoginController(LoginController loginController) {         this.loginController = loginController;     }      public void initialize(URL url, ResourceBundle rb) {         loginController =new LoginController();          try {             db = new DBConnector(); //            String user = loginController.getUser();             System.out.println(user);             String query = "SELECT u_full_name,img FROM Users WHERE u_username='"+user+"'";             db.setResultSet(query);             while(db.getResultset().next()){                 userName.setText(db.getResultset().getString(1));                 imageUpload.setImage(new Image("file:"+db.getResultset().getString(2)));             }         } catch (SQLException e) {             JOptionPane.showMessageDialog(null, "can't retreive photo",e.toString(),0);         }  }


Changing the Attribute table view in QGIS 3

How does one change the Attribute table view on QGIS 3? An initial answer says to use the Switch to Table view button but I can't seem to find this button.


Can I run NM-B inside EMT conduit for protection?

If I'm adding some new receptacles to a garage, and the wiring will be run surface-mounted to walls and ceilings, I think protecting the wiring with EMT conduit is probably a wise way to go.   I'm seeing some conflicting information as to whether it's OK to run NM-B (e.g. romex) inside EMT tubing. The more typical application is individual THHN conductors inside EMT. Rather than having to buy two types of wiring, is it OK to run the NM-B inside the EMT? Are there any special considerations?


Why do some questions not start with an auxiliary verb?

When I learned English, my teachers told me that all questions must have an auxiliary verb at the beginning, just like Are you mad? or Is she playing? do.  But when watching some movies or talking with people who speak English, they just ask using things like You mad? and She’s playing?   Of course, the kind of intonation let me know they are asking a question, but why this happen?


Hints to show that $A_{n}$ is nowhere dense in $C([0,1])$

Let $A_{n}:=\{f \in  C([0,1]): \exists x \in [0,1], \forall y \in [0,1] \operatorname{so that} |f(x)-f(y)|\leq n |x-y|\}$  I have already shown that $A_{n}$ is closed w.r.t $(C([0,1]), \vert \vert \cdot \vert \vert_{\infty})$ but now I want to show that $A_{n}$ is nowhere dense, and I am given the hint of considering the linear function $s:[0,1] \to [0,C]$ with slope $\pm(n + D)$ where $D$ and $C$ are some constants $> 0$.   $(\overline{A_{n}})^{c}=(A_{n})^{c}:=\{f \in C([0,1]): \forall x \in [0,1], \exists y\in[0,1] \operatorname{so that} |f(x)-f(y)|> n|x-y|\}$  Let $g \in C([0,1])$ and $ \epsilon > 0$: since $g$ is continuous for all $x \in [0,1]$ then there exists $\delta_{x} > 0$ so that for all $|x-y|< \delta_{x}\Rightarrow |g(x)-g(y)|<\epsilon$  $\vert \vert g - f \vert \vert_{\infty}=\sup_{x \in [0,1]}|g(x)-f(x)|$  I am unsure on how to use the linear function $s$. Any ideas?


I calculated the subgroups of $\mathbb Z / 2 \mathbb Z \times \mathbb Z / 2 \mathbb Z$ as $\{ (0, 0 ) \}, \{ (0, 0 ), ( 1, 0 ) \}, \{ (0, 0 ), (0, 1) \}, \{ (0, 0 ), (1, 1) \}$ and $ \mathbb Z / 2 \mathbb Z \times \mathbb Z / 2 \mathbb Z$ and itself. I  a bit and found couple of answers which did not include $\{ (0, 0), (1, 1)\}$. Isn't $\{ (0,0), (1,1)\}$ subgroup of  $\mathbb Z / 2 \mathbb Z \times \mathbb Z / 2 \mathbb Z$ ?


Moving files from bad external harddrive

I use OSX mavericks. My external 1TB harddrive is partially unreadable. I want to salvage its content as much as possible. I have tried dd but it took almost a day, so I killed it, and it could not resume from where it left when I rerun it. I am currently trying moving folders one by one with Finder.    My question is there any option in Finder to continue moving even if errors are detected ?


I have researched a lot about it, I made many tests and no success.  Here's what happens:  My database is now "utf8_unicode_ci". I did a simple test to register a name as "Gê" and the tables are accepting normally.  The problem is when I do it from my RegisterUser php file. The results in the table is this: G&ecirc;  My php connection with the database is:  public function openConnection() {      $this->conn = new mysqli($this->dbhost, $this->dbuser, $this->dbpass, $this->dbname);     $this->conn->set_charset("utf8");     if (mysqli_connect_errno()){         throw new Exception("Could not establish connection with database");     } }   PS: I've tried the latin1_swedish_ci format  Edit:  I fixed this using the following htmlentities: $username = html_entity_decode($_POST["username"], ENT_QUOTES, "ISO-8859-5");


How do you add aria attributes to a lightning base component?

I am implementing a component blueprint of the  component which needs aria attributes to properly toggle the chevron from being open and closed.   Let's say I need to add the attribute: aria-expanded="false" to the actual button tag. If there is a way to access the DOM and add this, how would I do this and at what part of the rendering cycle should it be added?  The base component looks like this:  <lightning:buttonIcon        iconName="utility:switch"       variant="bare"        alternativeText="toggle switch"        class="slds-m-right_x-small slds-m-top_x-small"/>   The html markup looks like this:  <button    class="slds-button slds-button_icon slds-m-right_x-small slds-m-top_x-small"    title="Toggle details for Add Users to Your Org"    aria-controls="step-0-summary-action"    aria-expanded="false">      <svg class="slds-button__icon slds-summary-detail__action-icon"         aria-hidden="true">         <use            xlink:href="/assets/icons/utility-sprite/svg/symbols.svg#switch">         </use>     </svg>   <span class="slds-assistive-text">Toggle details for Add Users to Your Org    </span> </button>


Are there any special rules when making a substitution in an integral?

Please consider the integral:  $$\int_{-a}^{a}x^2dx=\frac{2a^3}{3}$$  I would like to know why I can't make the substitution:  $$u=x^2$$  When I make the substitution, the limits of the integral will be the same, and the integral itself will be zero, which is the wrong answer. So why does this simple change of variables not work as I have expected?  Please note that I do not want help solving the integral, I know how to solve it several ways. My question is why does this specific attempt at a solution not work?


Simplifying the product $\prod\limits_{k=2}^n \left(1-\frac1{k^2}\right)$

Can we simplify the given product to a general law? $$\left(1-\frac{1}{4}\right)\left(1-\frac{1}{9}\right)\left(1-\frac{1}{16}\right)...\left(1-\frac{1}{n^2}\right)$$


Is there a formula to calculate the following sum?

I tried googling, but I may not be searching with correct terms.  $$\sum_{k=1}^{n} k^k = 1^1 + 2^2 +3^3 + 4^4 + \cdots + n^n$$  So, is there a formula to calculate this?


How do I specify a function without a defined argument?

A function $f$ with the argument $x$ is commonly written $f_x : A\to B, x\mapsto f(x)$, or $f_x : \mathbb{R} \to \mathbb{R}, x\mapsto x^2$, but say I don't want to specify the argument, how would I write this ? $f : \cdot\to\cdot, \mapsto ^2$ seems unnatural.


Question about the Lehmann-Kallen representation in Srednicki

So when deriving the LK form of the exact propagator he says (chapter 13): $$ \langle 0| \phi(x)\phi(y)|0\rangle=\int d\tilde k e^{ik(x-y)}+\int_{4m^2}^\infty ds\rho\int d\tilde ke^{ik(x-y)}. \tag{13.12}$$ My question is about the $4m^2$ cutoff, I get that this is the 2 particle mass, however, that is only true if they don't interact.  Surely there will be either some bound states just below that or, depending on if the particles attract or repel, this cutoff will be shifted? Does he just mean this approximately or am I missing something?


What is the correct verb for "driving" a boat?

How do you describe driving a boat? Is is correct to say   drive a boat steer a boat sail a boat?


Where is the ideal place to ask a MATLAB question?

For most cases the answer is either Stack Overflow or Cross Validated. But for my current , neither of them seem suitable. Is SU the right place? I also see MATLAB in Area 51, but I'm not sure if that site is actually for asking questions, or discussing the proposal itself.  So I would appreciate any help on where to ask such a specific question.


I've got a doubt with the below code. any help will be appreciable.  class Test {      static void test(List<Object> obj) {         obj.add(5);         obj = new ArrayList<>();     }      public static void main(String[] args) {          List<Object> list = new LinkedList<>();         list.add(10);         System.out.println(list);         test(list);         System.out.println(list);     } }   what will be the content of list object after test method returned to main method?    Expected Output:  [10]  [] //empty  since we are creating a new arraylist object in the same list reference which is passed to test method from main method.  Actual Output :   [10] [10, 5]  could please explain this?


All of the windows on my Windows 8 computer have started to lose focus every minute or so and get focus back quickly.  Any ideas what this could be?  I have tried to see which application is using most CPU when this happens, but to no success.  I am running a Norton scan at the minute, so that should sort out any malware.  It is starting to get VERY annoying!


I am trying to show that If $S,T$ are mappings from $V \rightarrow V$, where V is finite, then $Rank(S+T) \leq Rank(S) + Rank(T)$ after finishing a chapter entitled "Applications of Rank-Nullity".  First consider two lists of vectors $S(x_1),...,S(x_n)$ and $T(y_1),...,T(y_n)$  where the $x_i, y_i \in V$ the vectors are linearly independent then it seems to me that the basis S+T will have a trimmed down version of the combination of these two lists (i.e. getting rid of any redundant or linearly dependent vectors) thus its rank would be less than or equal to S(x) + T(x), but I am not sure how to write this in a more formal way. Any Hints appreciated including alternative methods of proof if I have gone off the rails here.


When is afternoon? When is evening? When is night? Is there another meal after dinner?

I'm a beginner here, and I have a question about the evening/night meal, and this is my first question.      It's evening. The family is eating dinner.    From when until when is it considered to be "evening" in English? And from when until when is it considered "night"? Are these completely distinct or are they overlapping concepts? I’m an Iranian. In Iran, we consider "evening" to run all the way from afternoon until sunset (4 pm – 8 pm), while "night" for us runs from right after sunset until the next sunrise; and we eat "dinner" at night, normally around 10 o’clock at night.   So, does one eat another meal after "dinner"? It seems to me that "dinner" is an evening meal and people eat it very soon, so it should be not the meal that people eat late at night, as we do in Iran.


To what extent I am free with my voting?  And - especially - with downvoting.   I came into argument with another user on the reasons for the voting. So, I decided to ask.  Beside usual awful no-research-effort questions and quick-and-wrong answers, I am often voted down for the answers you would call correct ones:   When I think there shouldn't be answer at all (helping the OP to shoot himself in the foot or feeding a help vampire)  To negate an over-upvoting craze for the silly answer on even more silly question.   So, the question is - what you think on these reasons?   And - bonus question - is there any difference in the policies for the voting up and down?


Including extensive SVG images, too many pages in the pdf?

I have a lot of svg images I want to include in a TeX-File.   So far I didn't have problems using the \usepackage{svg} with \includesvg.  However recently I've added a few more layers to the svg-files and now a lot of stuff is missing.   The resulting svg-tex.pdf files now have up to 61 pages and if I look into the svg-tex.pdf_tex files with texmaker I found the culprit: it only goes up to 50 pages:  \put(0,0){\includegraphics[width=\unitlength,page=50]{Sym_9999_svg-tex.pdf}}%   Putting the pages in manually like:   \put(0,0){\includegraphics[width=\unitlength,**page=51**]{Sym_9999_svg-tex.pdf}}%   does work, but would be very time inefficient (I have 100+ svg images) additionally the layers don't have the correct sequence and cover up text sometimes.   Does anyone have a solution for this problem?   If I open up the svg-image it shows up just fine.   One possibility would be to just export the svgs in one pdf file without the text as extra latex file, but this way I can't add formulas in Tex-Form.


Can I filter and sort email ids in notepad++ and other text editors?

I have a txt file which has around 20000 email id. I want to know email count from gmail, yahoo, ymail, googlemail, aol, live,custom domain, gmx, and other temporary emails separately. And also i need to filter them and sort them in email domain order. How can i do that using notepad++? If any other program make this much easier than notepad ++  please refer that too.


Can there be a lottery of the natural numbers?

Can there be a lottery of the natural numbers, so that every natural number is chosen equally likely?   The standard answer would be "No" because: If we define a measure $\mathbf{P}$ on $\mathbb{N}$ so that $\mathbf{P}(n) = r \in (0,1] \; \forall \, \mathbb{N}$, then $\mathbf{P}(\mathbb{N}) = \infty$. If we define a measure so that $\mathbf{P}(n) = 0$, then $\mathbf{P}(\mathbb{N}) = 0$.  But why can we conclude from that, that a lottery of the natural numbers (with every natural number equally likely) is impossible?  Note: the question is not if there can be a uniform probability distribution (satisfying all axioms of probability, including countable additivity) over the natural numbers but if there can be a lottery of the natural numbers so that every number is chosen equally likely!


UV Maps not preserved after Boolean Modifier

I have multiple objects I need to boolean together, but when I apply the modifier, the UV maps get messed up in a very odd manner. It is actually visible before the modifier is applied.  Two Objects:    Before Application:    UV Map afterwards:    I can't for the life of me figure out what the problem is. I checked the face normals, made sure the meshes were manifold and applied all materials to the objects in multiple configurations.


How can I converge the touchpad and touchscreen interface?

Basically I want to begin migrating my Macbook Pro to Ubuntu Touch, while only making changes in the GUI. I need to expose the apple touchpad to the desktop as a touch surface, rather than mouse.


Javascipt component not coming render as pdf

I am working on a visualforce page and have used javascript to add a row dynamically. All are coming in the pdf except that javascript column.  Below is the javascript sippet that is not loading:  <apex:page controller="Controller" renderAs="pdf">    <html xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">          <script src="https://code.jquery.com/jquery-1.11.1.min.js"></script>         <!--SLDS STYLESHEET STATIC RESOURCE-->             <apex:slds />                 <body>


How do I install 32 bit driver on windows 7 64 bits? (for canon faxphone L75)

I have a computer with windows 7, 64 bits.  I also have a Canon Faxphone L75 for which I only can find 32 bit drivers.  How can I fix this?


I want to compute the following ratio: $$\frac{\int_0^1x^n\sqrt{1-x^2}}{\int_0^1x^{n-2}\sqrt{1-x^2}}$$  As I found from wolframe it is $\frac{n-1}{n+2}$. I am trying to solve the integral using the following substitution:  $$f(x) = x^{n-2}\sqrt{1-x^2}$$ $$\frac{\int_0^1x^2f(x)}{\int_0^1f(x)}$$  But I am sticking here.


How do you figure out the max amount of spells that can be prepared?

I have a druid character, and I want to find out how many spells I can prepare at any one time.


Just as some background - it was an animated cloth object with physics, collision, and some hooks.  I "applied" all the modifiers when I liked its look, but now I'm searching for some setting that is keeping it from rendering.  Originally I was using cycles engine to apply materials, but I switched to the blender renderer and applied a new material.  Could this have been the problem?


Apple pulled Mojave 10.14.0 -- Where can i get it? -- 10.14.4,,,10.14.6 etc., are still available from Apple

I cannot upgrade to MOJAVE.  After spending a lot of time searching through Apple's download site, I contacted Apple support and they told me that I cannot download Mojave 10.14.0.  That version has been removed from their download files.  Other later versions are still available.  However, I CANNOT INSTALL 10.14.4 OR 10.14.6 without first installing 10.14.0.  Are there any non Apple sites that make that 10.14.0 download available?????


My code: #include <iostream>  using namespace std; int main() {     unsigned int  a = 0x0009, b = 0x0002;     unsigned int  c = a + b;     cout << c; }  Now c = 11  I want to this: c = 000B  How can I do ?


In French the word I'd use is mes connaissances. But this word also (and mainly) means the things I know, and then the traduction I find is: my knowledges.  Is this double meaning exists in English and what should I say to talk about people I know and who know me without being my friends?  Edit (an example of context):     This software is very popular, if you have any problem with it just ask to your connaissances, I think that somebody could help you.


Right form of the question about past:  Example:   Do you thought about... Did you think about... Did you thought about...   Or which to use and when?


Convergent or divergent: $\sum_{k=1}^{\infty}\frac{2^{k}\cdot k!}{k^{k}}$

Convergent, absolutely convergent or divergent:   $$\sum_{k=1}^{\infty}\frac{2^{k}\cdot k!}{k^{k}}$$   I have used ratio test because we got a fraction here and I think I did alright till the end:  $$\lim_{k\rightarrow \infty}\frac{\frac{2^{k+1}\cdot (k+1)!}{(k+1)^{k+1}}}{\frac{2^{k}\cdot k!}{k^{k}}} = \lim_{k\rightarrow \infty}\frac{2^{k+1}\cdot (k+1)! \cdot k^{k}}{(k+1)^{k+1}\cdot 2^{k}\cdot k!} = \lim_{k\rightarrow \infty}\frac{2^{k}\cdot 2^1\cdot k! \cdot (k+1)\cdot k^{k}}{(k+1)^{k}\cdot (k+1)\cdot 2^{k}\cdot k!} = \lim_{k\rightarrow \infty}\frac{2k^{k}}{(k+1)^{k}}$$ $$=2\lim_{k\rightarrow \infty} \left( \frac{k}{k+1}\right)^{k}$$  Now I don't know (without a calculator) to what this would converge / diverge to... In the exam we are not allowed to use a calculator... So what to do?  The denominator will be greater than the enumerator by 1, so dividing each other we got something $<1$. We take exponent $k$ which is $\geq 1$, so we will end up with $<1$ again. Multiply this with 2 we get something $< 1$ but $> 0$ and thus the series is convergent...?  I hope I have described it well? Would you give me full points to this task? :D  Edit: I haven't described it well in the end. See the accepted answer and its comments! Thanks a lot to everyone - from every question I ask here, I always learn new things :-)


tl;dr  We rolled out some improvements for how you track the topics you are interested in for your favorite Q&A sites. This feature used to be called Favorite Tags. We are renaming it Tag Watching. Naming is hard, but we think this better captures the value of the feature. There were a number of confusing elements to the old feature. We've attempted to clear these up and refocus the user experience on the core functionality.     This feature is live as of today (07/26/2018) on all sites. We turned this on for all sites earlier than expected so that we could do some code cleanup.   Key improvements:   Released   On boarding: new users are introduced to tag watching and how it can help them Cleaner pop up: new pop up is more focused on the key actions.  Coming later   Notifications: When watching a tag you're prompted to set up notifications, if desired. Also, changing notification settings will be supported when you edit your watched tags in the right side bar.    On boarding  Many users don't actually favorite any/many tags. Part of this is likely due to fact that we never explained why you should bother. In the old system all you saw was:  Tag Favorites on boarding    Now you see a description of the value tag watching provides.    Tag pop up  Our old tag pop up was very comprehensive and confusing. So many options. Watching/ignoring a tag was a tristate button (those are never a good option). An every action is essentially presented on equal footing. This makes it really hard for new users to understand what they can/should do.    The new pop up is focused on two primary actions (watch or ignore tag) and two minor actions (view tag, access RSS).    Notifications (coming later)     We have some work to make the notifications scale to SO. So, while these improvements are live for Teams users, they will be enabled later (timing TBD) for SO and the rest of the network.    With the old system watching a tag and getting notifications were two separate steps. With the new experience, you will be prompted to set your notifications when you watch a tag.    Also, changing your notifications will be integrated into the experience of editing your watched tags.    Feedback wanted  As usual, we are happy to hear your constructive feedback. Feel free to post an answer below if you think of an improvement.


Rankings of the historic universities in Europe

I am surprised that some of the most historic universities in continental Europe are ranked above 100 on an average. I specifically have in mind University of Gottingen and University of Vienna. I am assuming that at the peak of their fame, they were rubbing shoulders with the best in the anglo-sphere. What caused the slide in reputation? I have heard that in Germany, Nazism caused the emigration of a lot of talented people. Or is it just that the ranking methodology is biased towards universities in the UK and the US? As someone interested in the history of scientists and scientific institutions, it seems somewhat odd.


Convert from Nested Square Roots to Sum of Square Roots

I am looking for a way to easily discover how to go from a nested root to a sum of roots.  For example,   $$\sqrt{10-2\sqrt{21}}=\sqrt{3}-\sqrt{7}$$  I know that if I set $\alpha=\sqrt{10-2\sqrt{21}}$, square both sides, I get  $$\alpha^2=10-2\sqrt{21}$$  Now I recognize that we have a situation where $10=3+7$ and $21=7\cdot 3$, so I can immediately see that we have  $$\alpha^2=10-2\sqrt{21}=3-2\sqrt{21}+7=\sqrt{3}^2-2\sqrt{3}\sqrt{7}+\sqrt{7}^2=(\sqrt{3}-\sqrt{7})^2$$  My question is, it this the only way to approach this problem?  This approach mirrors basic algebra 1 methods of factoring quadratics, but I was curious to know if thre are other techniques that can be used to quickly deduce that a nested radical can be simplified to the sum of two radicals.  Mathematically, suppose $a,b,c,m,n,r,s\in\mathbb{N}$.  Is there a way to quickly determine $m,n,r,s$ in the equation  $$\sqrt{a\pm b\sqrt{c}}=m\sqrt{r}\pm n\sqrt{s}$$


Extra White Space after iftenelse in Title

To begin, here is a MWE:  \documentclass[12pt]{article}  \usepackage{float} \usepackage{tikz} \usepackage{subfig} \usepackage{ifthen}  \begin{document}  \newcommand{\titlename}[1] {     \ifthenelse{\equal{#1}{a}}{First}{}     \ifthenelse{\equal{#1}{b}}{Second}{} }  \foreach \y in {a,b}{     \foreach \a in {No,Yes}{             \begin{table}[H]         \captionsetup{width=.9\linewidth}         \caption{\protect\titlename{\y}, \a  ~Other Text}         \end{table}     } }  \end{document}   This produces captions:  Table 1: First , No Other Text Table 2: First , Yes Other Text Table 3: Second , No Other Text Table 4: Second , Yes Other Text   My question is simple: How can I get rid of the extra space after First and after Second? In other words, the comma should directly follow First and Second as the case may be.


Changing parameter values according to other parameter choice in Processing script using QGIS 3?

I couldn't find anything about this problem.  Suppose to have the first parameters in a Processing script defined as an Enum:     self.addParameter(         QgsProcessingParameterEnum(             self.CHOICE,             self.tr('Choose the parameter'),             ['param1', 'param2']         ) )   While the second one as a number:  self.addParameter(     QgsProcessingParameterNumber(         name=self.VALUE,         description=self.tr('My value'),         type=QgsProcessingParameterNumber.Double,         defaultValue=40,         optional=False,         minValue=0,         maxValue=100     ) )   Is it possible to change the minValue, maxValue, description, ecc.. of the second parameter depending on the first or second choice of the first parameter already in the GUI?  e.g. if the user choose param1 then the second parameter should become:  self.addParameter(     QgsProcessingParameterNumber(         name=self.VALUE,         description=self.tr('My value'),         type=QgsProcessingParameterNumber.Double,         defaultValue=40,         optional=False,         minValue=0,         maxValue=100     ) )   while if he choose param2 it should became:  self.addParameter(     QgsProcessingParameterNumber(         name=self.VALUE,         description=self.tr('My AWESOME value'),         type=QgsProcessingParameterNumber.Double,         defaultValue=0,         optional=False,         minValue=50,         maxValue=500     ) )


When I use my data for Pokémon GO, no Pokéstops or Pokémon in the sightings appear just the road and the avatar walking however when I use WiFi or hot-spot, the Pokéstops and Pokémon appears again. I have been facing this problem just 3 days ago and I can't play without WiFi or hot-spot. What should I do? I have tried deleting the game and almost everything.


I am and my friend working on the same project, he has ssh permission for repo, he gave me his ssh key and I want to import it to my  id_rsa.pub, but after I get Permission denied error when want to clone project. Can somebody help me? Thanks!


Someone is trying to brute force SSH access to my server

By coincidence I looked at my servers ssh log (/var/log/auth.log) and I noticed that someone is constantly trying to gain access:   Sep  7 13:03:45 virt01 sshd[14674]: pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=116.31.116.42  user=root Sep  7 13:03:48 virt01 sshd[14674]: Failed password for root from 116.31.116.42 port 13423 ssh2 Sep  7 13:03:52 virt01 sshd[14674]: message repeated 2 times: [ Failed password for root from 116.31.116.42 port 13423 ssh2] Sep  7 13:03:52 virt01 sshd[14674]: Received disconnect from 116.31.116.42: 11:  [preauth]   This happens a few times every minute, and has been going on for a long time without me knowing about it.   Question Should I be concerned about this, if yes: What should I do about it?


Is it bad that my MacBook Air is passing me electricity?

Whenever my MacBook Air is connected to the AC power and I have my hands on the palm rest, I feel it passes some electricity to me. If I unplug it from the AC power it stops doing that.  This has recently became obvious, when other people can feel this tingling by touching my skin after I've been working for a while.  I have two questions:  1- Is this normal in unibody Macs?  2- Is this harmful for my health in the long run?


I am not really sure how to do this question, I think it has something to do with setting up a matrix for Gaussian reduction so that you can find what $q,r,s,t$ need to be so that the following is true: $$ (a_1,a_2,a_3,a_4) = q\vec{u_1} + r\vec{u_2} + s\vec{u_3} + t\vec{u_4} $$ Is there something to do with span as well?


iMac data recovery - file icon with ? mark

My iMac went dead, and was trying to recover data from it by connecting Thunderbolt.  The dead iMac's hard drive did not appear on the other Mac. As a next step, I was trying to reboot to use Disk Utility for Target Disk mode, when my iMac showed this blinking icon with file and question mark.  What does this mean and what am I supposed to do?


The ideal $(x,y)$ is not a free $K[x,y]$-module

Given a field $K$ we have the polynomial ring $K[x,y]$ in $2$ variables, which is also a left module (over itself). How can we prove that the ideal $(x,y)$ is not a free module?


What's the standard way to promote questions to Twitter?

Suppose I see a post on say Electronics SE which I think should be tweeted on Electronics SE Twitter account.  So far I was flagging such questions for moderator attention commenting that the question would be great for tweeting. I'm not sure it's the best way.  What's the conventional way I should follow for this purpose?


Limiting value of a sequence when n tends to infinity

Q) Let, $a_{n} \;=\; \left ( 1-\frac{1}{\sqrt{2}} \right ) ... \left ( 1- \frac{1}{\sqrt{n+1}} \right )$ , $n \geq 1$. Then $\lim_{n\rightarrow \infty } a_{n}$  (A) equals $1$  (B) does not exist  (C) equals $\frac{1}{\sqrt{\pi }}$  (D) equals $0$    My Approach :- I am not getting a particular direction or any procedure to simplify $a_{n}$ and find its value when n tends to infinity. So, I tried like this simple way to substitute values and trying to find the limiting value :- $\left ( 1-\frac{1}{\sqrt{1+1}} \right ) * \left ( 1-\frac{1}{\sqrt{2+1}} \right )*\left ( 1-\frac{1}{\sqrt{3+1}} \right )*\left ( 1-\frac{1}{\sqrt{4+1}} \right )*\left ( 1-\frac{1}{\sqrt{5+1}} \right )*\left ( 1-\frac{1}{\sqrt{6+1}} \right )*\left ( 1-\frac{1}{\sqrt{7+1}} \right )*\left ( 1-\frac{1}{\sqrt{8+1}} \right )*.........*\left ( 1-\frac{1}{\sqrt{n+1}}    \right )$     =$(0.293)*(0.423)*(0.5)*(0.553)*(0.622)*(0.647)*(0.667)* ....$ =0.009*...  So, here value is tending to zero. I think option $(D)$ is correct. I have tried like this $\left ( \frac{\sqrt{2}-1}{\sqrt{2}} \right )*\left ( \frac{\sqrt{3}-1}{\sqrt{3}} \right )*\left ( \frac{\sqrt{4}-1}{\sqrt{4}} \right )*.......\left ( \frac{\sqrt{(n+1)}-1}{\sqrt{n+1}} \right )$ = $\left ( \frac{(\sqrt{2}-1)*(\sqrt{3}-1)*(\sqrt{4}-1)*.......*(\sqrt{n+1}-1)}{{\sqrt{(n+1)!}}} \right )$ Now, again I stuck how to simplify further and find the value for which $a_{n}$ converges when $n$ tends to infinity . Please help if there is any procedure to solve this question.


Discreteness of the universe and evidence for simulation

To my untrained thinking, the Planck length / Planck time implies there is a fundamental granularity or quantisation to the universe. In other words, the universe has a certain “resolution” such that matter cannot occupy the space between Planck lengths. I suppose this would imply an absolute grid of some kind. As a computer programmer, my interest in this comes from thinking that it might support the idea that we’re in a simulation. The other thing that may support this is the many-worlds interpretation of the wave function collapse. If something was wanting to simulate all possibilities in our universe, branching the simulation at the most fundamental level (the wave function) would make sense. Discreteness also makes sense in order to have the simulation require a finite (but mind boggling) amount of memory, assuming there is no purely analytical description of it. Final thought: holographic projection could be a compression technique they are using ;) Short version of the question: is the universe fundamentally discrete?


Word for romantic partner you are living with but not married to

What is a word for a person you live with but are not married to? I do not mean a room mate, but rather someone you are romantically involved with. From what I understand, spouse is someone you are married to and boyfriend/girlfriend does not state that you live together.


"Turquoise-haired"—(-ed) suffix attached to a noun

I found this sentence on       Amber Rose hangs out with (a) turquoise-haired mystery girl.    I couldn't find 'turquoise-haired' in any dictionary, but a similar construction, "", has its place in Collin dictionary.   I don't understand how it's possible to attach the -ed suffix to a noun. Do we have a fancy term for this?


Problems with rendering references sections correctly

I have a generated a minimal reproducible example and I just can't get it to work as I want. When I run this example it will basically replace the name of the authors in the reference list with a straight line. Is this by design? If I just add any letter to any of the author names it gets displayed as I want it. The first reference is a generic book reference while the second is a page reference. This is the contents of the tex-file \documentclass[12pt]{article}   \usepackage{authblk} \usepackage[utf8]{inputenc} \usepackage{csquotes}  \usepackage[swedish]{babel} \usepackage[style=ieee]{biblatex} \addbibresource{references.bib}   \begin{document}  \title{Projektrapport} \author{   Name 1, Name 2, Name 3 } \date{2020-XX-YY}  \maketitle  \section*{Introduktion} Hello \cite{stokastik} World \cite{stok1}  \printbibliography  \end{document}  This is the contents of the references.bib file @book{stokastik,     author      = "Sven Erick Alm and Tom Britton",     maintitle   = "Stokastik Sannolikhetsteori och statistikteori med tillämpningar",     volume      = "1",     title       = "Stokastik",     publisher   = "Liber",     year        = "2018",     ISBN        = "978-91-47-05351-3", }  @inbook{stok1,     author      = "Sven Erick Alm and Tom Britton",     title       = {Stokastik Sannolikhetsteori och statistikteori med tillämpningar},     volume      = "1",     publisher   = "Liber",     year        = "2018",     pages       = {72-89,69, 112,22},     edition     = "second",     ISBN        = "978-91-47-05351-3", }


How do I enable https with httplistener?

I am trying to create a simple https server in c# in a Unity3D game, to be accessed through a web browser. I've created a server cert and key with openssl, but I can't find a multi-platform way to pass the cert to the server without any additional configuration outside the code.  Most of the info I've been able to find falls into these categories:   Uses SslStream, but that seems to only be relevant for TcpListener (and I want something higher level that can serve webpages) Requires external Windows-only tools like httpcfg that I'd prefer not to use Programmatically or manually installing certs in certificate stores, which seems to require either the program or the user to have admin/root privileges   I know in python you do something like:  ssl.wrap_socket (httpd.socket, certfile='./server-crt.pem', keyfile='./server-key.pem', server_side=True)   ...but there doesn't seem to be an equivalent in c# for httplistener, or in system.security.securitymanager or anything. I assume/hope that I'm just missing something obvious here.  For what it's worth, here's what I have so far, which is just the MSDN httplistener example put in a Unity script:  using System.Collections; using System.Collections.Generic; using UnityEngine; using System; using System.Net;  public class SimpleListenerExample : MonoBehaviour {      // This example requires the System and System.Net namespaces.     public static void StartServer(string[] prefixes)     {         if (!HttpListener.IsSupported)         {             Console.WriteLine("Windows XP SP2 or Server 2003 is required to use the HttpListener class.");             return;         }         // URI prefixes are required,         // for example "http://contoso.com:8080/index/".         if (prefixes == null || prefixes.Length == 0)             throw new ArgumentException("prefixes");          // Create a listener.         HttpListener listener = new HttpListener();         // Add the prefixes.         foreach (string s in prefixes)         {             listener.Prefixes.Add(s);         }          /* and here's the part where I would load the server certificate ...somehow */          listener.Start();         Console.WriteLine("Listening...");         // Note: The GetContext method blocks while waiting for a request.          HttpListenerContext context = listener.GetContext();         HttpListenerRequest request = context.Request;         // Obtain a response object.         HttpListenerResponse response = context.Response;         // Construct a response.         string responseString = " Hello world!";         byte[] buffer = System.Text.Encoding.UTF8.GetBytes(responseString);         // Get a response stream and write the response to it.         response.ContentLength64 = buffer.Length;         System.IO.Stream output = response.OutputStream;         output.Write(buffer, 0, buffer.Length);         // You must close the output stream.         output.Close();         listener.Stop();     }      // Use this for initialization     void Start () {         String[] prefixes = { "http://*:8089/", "https://*:8443/" };         StartServer(prefixes);     }      // Update is called once per frame     void Update () {      } }


I'm trying to show that  $$\delta\big(f(x)\big) = \sum_{i}\frac{\delta(x-a_{i})}{\left|{\frac{df}{dx}(a_{i})}\right|}$$  Where $a_{i}$ are the roots of the function $f(x)$. I've tried to proceed by using a dummy function $g(x)$ and carrying out:  $$\int_{-\infty}^{\infty}dx\,\delta\big(f(x)\big)g(x)$$  Then making the coordinate substitution $u$ = $f(x)$ and integrating over $u$. This seems to be on the right track, but I'm unsure where the absolute value comes in in the denominator, and also why it becomes a sum.  $$\int_{-\infty}^{\infty}\frac{du}{\frac{df}{dx}}\delta(u)g\big(f^{-1}(u)\big) = \frac{g\big(f^{-1}(0)\big)}{\frac{df}{dx}\big(f^{-1}(0)\big)}$$  Can any one shed some light? Wikipedia just states the formula and doesn't actually show where it comes from.


Hp Laserjet Mfp 436 printer installation issue in ubuntu 16.04

I have a printer Hp Laserjet Mfp 436 nda, I am unable to install the printer drivers in hplip-gui ubuntu 16.04, 14.04 & 12.04 because the mfp 436 model is not available while installing the drivers. I need help how to install the drivers.


Omitting an implied article, or avoiding repetition

If I say "The boy and girl are..."  I think it's as correct as "The boy and the girl", as some natives told me that.  Do you confirm?  But what is the rule in English for non repeating the article?    And also, more generally, are there other rules for omitting the singular article? When could it be implied? (I don't mean the zero article, like in generalities, categories and plural, when we expect the zero article.)


Question: $\boxed{\text{Consider $\sum_{i=1}^{100}\tfrac{1}{i}=\tfrac{A}{B}$. Given that $\text{gcd}(A,B)=1$,  Show that $5\nmid AB$}}$


$0 = 0 + 0 + 0 + ...$   $0 = (1 - 1) + (1 - 1) + (1 - 1) + ...$   $0 = 1 - 1 + 1 - 1 + 1 - 1 + ...$   $0 = 1 + (-1 + 1) + (-1 + 1) + (-1 + ...$   $0 = 1 + 0 + 0 + 0 + ...$   $0 = 1$   I can't really tell what is obviously wrong with this. It seems to use the same logic as we see in the derivation of things like $\sum_{k=1}^{\infty} k = -\frac{1}{12}$ which appears to be a quirky but accepted fact in mathematics.


Please allow tag filtering on the new review pages

I think it could be a good idea to allow tag filtering on the new review pages. There is already a  asking for the review pages to be ordered randomly since there are so many to review that some could get lost in the shuffle. I think that allowing users to filter based on tags could help, since a lot of answerers watch their own niche of questions, and would be better able to identify a question as a dupe than Random J. User might.  On a personal note, I think this could be good for me since I'd really like a snowballs chance of getting [Tenacious] and [Unsung Hero], and I've noticed that brand new users sometimes don't realize they can vote/accept answers, so if you gently guide them to the accept button but don't mention voting, you can sometimes get a zero-accept out of them. ;)


Should a UI say "My Stuff", or "Your Stuff"?

I've been getting some different opinions on this question, and wondered if anyone has a well-motivated response. Basically, if I have a part of a website that's called "My something" or "Your something", I feel that it sets a very different conversational tone of the UI.  "My", would mean that I'm the one saying it, meaning in a way I'm taking ownership of the UI as a user. If the menu item is called "Your", then it's the website presenting this area to me, meaning it contains my things, but it's the website that owns it.  I'm personally leaning more towards using "Your", since at least in the beginning of the user using this website the user will not feel at home in the system, making things like "My" feel a bit off. On the other hand, it seems like "Your" is less of a standard approach, so maybe this matter has already been decided and I just haven't found any good resources on it


How do we determine who is the "observer" when calculating time dilation?

I was reading about time dilation and I thought of a question. I really think that I am just misunderstanding something, so please bare with the question. But, I would appreciate if somebody could help me understand this better.    Consider Alice is on earth and Bob is flying past earth in a spaceship going 97% the speed of light. Four minutes of Alice's lifetime would elapse in one minute of Bob's lifetime, as given by the equation:    1/0.243 ≈ 4  Here, Alice is the observer. Bob's velocity is relative to Alice who is assumed to be stationary.  But, what if we look at things from Bob's perspective. If we assume that Bob's velocity is 0, then that would mean Alice is flying past him in the opposite direction at 0.97c.  In this case would we say that four minutes of Bob's lifetime elapse in one minute of Alice's?  That does not seem possible, since it would have to be one or the other, right?    What obvious point am I missing here?