Why do we define quotient groups for normal subgroups only?

Let $G \in \mathbf{Grp}$, $H \leq G$, $G/H := \lbrace gH: g \in G \rbrace$. We can then introduce group operation on $G/H$ as $(xH)*(yH) := (x*y)H$, so that $G/H$ becomes a quotient group when $H$ is a normal subgroup. But why do we only work with quotient groups by normal subgroups? If we introduce the notion of left quotient group in the above manner, how much good properties of a quotient group do we lose?


How to solve the following problem in Linear Algebra?

Let $A\in M_3(\mathbb R$) which is not a diagonal matrix.   Let $p$ be a polynomial  (in one variable), with real coefficients and of degree $3$ such that $p(A) = 0$.  Pick out the true statements:  (a) $p = cp_A$ where $c\in \mathbb R$ and $p_A$ is the characteristic polynomial of $A$  (b) If $p$ has a complex root (i.e. a root with non-zero imaginary part), then     $p = cp_A$, with $c$ and $p_A$ as above  (c) If $p$ has a complex root, then $A$ is diagonalizable over $\mathbb C$.  I know if (b) holds then (c) will also hold.  Is there any relation between the characteristics polynomial and any other polynomial? I know that minimal polynomial will divide any other polynomial.  But how to think about these kind or problems?


When multiple edits are coalesced, does that mean only one bump?

If I write an answer, then edit it 4 minutes later, it doesn't show up as edited. Does it still bump the question?  Similarly, if I edit my answer, and then re-edit it again 4 minutes later, it only shows up as one edit in the history;* does it bump the question once, or twice?  At least on SO's front page and more active tags, a question could easily have fallen pretty deep in 4 minutes, and I don't want to accidentally drag it back to the top just to fix a typo in my last edit.    * As a side note, what is this edit-coalescing feature called? Obviously not "edit coalescing", because searching for "coalesce edit" or "edit coalescing" only turns up 5 results, only one of which refers to this feature…


Highlight unanswerable questions (i.e closed, on-hold, dupe etc)

Problem  When looking through the question listings, it's frustrating having read an entire question's title to then at the end find "[on-hold]" or "[duplicate]" etc. And so wasted time reading the title as I won't be looking at the question.    The area (end of title) is often quite busy with the question's snippet text close below, and previous question's user badges/profile image close above. So it's usually not immediately obvious without glancing over to see if a question is answerable or not (ie not on-hold etc).    I sometimes glance at the right side first, but then that's pointless with the ones which aren't closed/on-hold etc.    Request  Can we have some sort of unique highlight specifically to show when a question is on-hold, dupe etc, and so is not answerable?    Such as on-hold/closed/duped questions have their entire listing all light grey background, or some border, or whatever?    Even the notifications ([on-hold], [duplicate] etc) being a different colour to the title would be a massive improvement and make them stand out.    Actually, the [on-hold], [duplicate] etc being a different colour to the rest of the title would also separate them from user text and make them look more like serious sitey-notification-stuff. A possible double benefit.    Frequency  It might not be much of a problem on some tag(s), but there are plenty of tags where questions are closed/on-hold quite often, and this issue is frequent.    Spend a day in SO [php] and you'll see the issue. Programmers site seems to suffer a similar issue, as all the data on the question list page is quite squashed together (not a problem in itself, just worsens the issue I've raised here).      Note: Maybe I'm just getting old, and/or need new glasses.    EDIT  My question is different to the proposed dupe because the other question suggests having a yellow notification colour on the left hand side when a question is on-hold/dupe etc.     The suggestion in the other question does not solve my issue as then I'd have to look left on every question to check if the question is answerable or not. This is no better than my having to look right, as currently. The proposal in the other question is not ideal because it introduces another colour in an area already containing some colours. It could get confusing having too many colours there. I have suggested very different solution ideas.


Can someone explain me the origin of the sound from this YouTube video (link given)?

I think this question is not completely out of topic so I am showing the courage to ask the community for help as I don't formally understand the reason. Today I was going through this , from channel , but I can't understand the reason behind the origin of this type of sound. Is it just a unusual thing as mentioned or there is something specific physicis or Physical intuition behind it( obviously there is physicis)? Then what is it?


How to route traffic to different interfaces for different ports

I have an eth0 connection providing internet connection through a proxy server only for port 80 and 443 (provided by university). For ssh, git and related purposes, I got a different connection on my mobile connected to the laptop through wlan0 (or usb0 through tethering.)  I need to route all connections for port 80 and 443 through eth0 ethernet while the rest of the ports should connect through wlan0 or usb0.  I have searched online but only found about routing specific servers through specific interfaces using route command.  How to do a similar thing for different ports?


Through experience I've seen that the following statement holds true: "$A^TA$ is always a symmetric matrix?", where $A$ is any matrix.  However can this statement be proven/falsefied?


Shortest question to ask when you want to know whether the one you talk to is the eldest, second, third...or youngest child in his/her family.

I’ve always been asked by my Filipino friends how I should say the Filipino question “Pang-ilan ka sa magkakapatid?” in English.  You ask that question when you want to know whether someone is the eldest, second, third...or youngest child in the family. What’s the shortest way to ask such question without necessarily mentioning choices (eldest, second, etc.) as the Filipino question also does not mention the choices?


Bug in Keil ARM compiler with interrupt handlers and C++?

I have a problem with writing interrupt handlers in Keil ARM compiler for LPC1114. When I write program in C++ and specify --cpp compiler option all code from interrupt handlers disappears, it is replaced with infinite loop. I wrote simple program that illustrates my trouble.  #include "LPC11xx.h"           // LPC11xx definitions #define SYSTICK_DELAY 120000   // for 10 ms systick @ 12MHz osc  void SysTick_Handler(void) {   __NOP(); }  int main (void)  {   SystemInit();                   // from system_LPC11xx.c   SysTick_Config(SYSTICK_DELAY);  // from core_cm0.h   // Loop forever   while (1) __NOP(); }   When trying to compile this code with --cpp compiler option I get infinite loop in disasm:  SysTick_Handler PROC             EXPORT  SysTick_Handler           [WEAK]             B       .             ENDP   This is the place where __NOP() from above program must be. And it is there when I'm compiling code with --c99 compiler option or without additional options. Keil MDK version is 4.12. Can anyone tell me is there any solution or workaround ?


Clarification about daily cap and accepted answers

I read in  and that it does not include accepted answers. However it can be read in 2 ways:   The 15 points for accepted answer is not included The upvotes on accepted answer are not included   Which way of reading is correct? Could the FAQ be clarified?


Why the first moment is standardized before computing higher moments, but higher moments are not?

:     For the second and higher moments, the central moments (moments about the mean, with c being the mean) are usually used rather than the moments about zero, because they provide clearer information about the distribution's shape.   Could someone explain/convince me why this is true? Why is there a discrepancy? This has always bugged me and I have never seen a good explanation for it -- I just don't quite understand why/how standardization provides "clear" information in one case but not in another.  For example:     To compute the skewness, why not standardize both the mean and the variance?   To compute the kurtosis, why not standardize the mean, the variance, and the skewness? ... To compute the nth moment, why not first standardize all the mth moments for m < n? If standardization is useful then why only do this for m = 1?


$\prod_{k=1}^n (1+ \frac{z}{k})$ converges to $0$ when $\Re (z)<0$

We have a complex number $z$ such that $\Re (z)<0$ and the sequence $ z_n = \prod_{k=1}^n (1+ \frac{z}{k})$. Prove that $\lim_{n \rightarrow \infty} z_n = 0$.    How to do it? I guess it will be easier to prove that $\lim_{n \rightarrow \infty} |z_n|^2 = 0$, it's a trick that usually helps, but even though I thought about if for a longer while, I don't know how to prove it. May somebody help?


Is $\mathbb{Z}_p \times \mathbb{Z}_p$ a field when $p$ is prime?

Initially I thought that it is but in  a solution to a problem, it was said that $\mathbb{Z}_7 \times \mathbb{Z}_7$ is not a field, because it is not an integral domain due to the fact that: $(7,7) \cdot (1,1)=(0,0)$, which seems wrong to me because $(7,7)=(0,0)$.


Does there exist a way to determine the exact file that contains an allocation unit in a filegroup of multiple files?

I was hoping to get a granular view of which database files contained which allocation units for the various HoBTs (both aligned and non-aligned) living in a database.  The query I've always used (see below) has served me well until we began creating multiple data files per filegroup and I'm only able to figure out how to get as granular as the filegroup level.   select      SchemaName = sh.name,      TableName = t.name,      IndexName = i.name,      PartitionNumber = p.partition_number,     IndexID = i.index_id,     IndexDataspaceID = i.data_space_id,     AllocUnitDataspaceID = au.data_space_id,     PartitionRows = p.rows from sys.allocation_units au join sys.partitions p     on au.container_id = p.partition_id join sys.indexes i      on i.object_id = p.object_id     and i.index_id = p.index_id join sys.tables t      on p.object_id = t.object_id join sys.schemas sh     on t.schema_id = sh.schema_id where sh.name != 'sys'     and au.type = 2 union all  select      sh.name,      t.name,      i.name,      p.partition_number,     i.index_id,     i.data_space_id,     au.data_space_id,     p.rows from sys.allocation_units au join sys.partitions p     on au.container_id = p.hobt_id join sys.indexes i      on i.object_id = p.object_id     and i.index_id = p.index_id join sys.tables t      on p.object_id = t.object_id join sys.schemas sh     on t.schema_id = sh.schema_id where sh.name != 'sys'     and au.type in (1,3) order by t.name, i.index_id,p.partition_number;   However, this query won't work when there are multiple files in a filegroup as I can only get so far as to relate an allocation unit to a data space and, ultimately, a filegroup. I'd like to know if there's another DMV or catalog that I'm missing that I can use to further identify which file in the filegroup contains an allocation unit.  The question behind this question is that I'm trying to evaluate the actual effects of compressing partitioned structures. I know I can do a before-and-after using FILEPROPERTY(FileName,'SpaceUsed') for the file and a before-and-after on sys.allocation_units.used_pages/128. to get this information, but the exercise itself made me wonder if I could identify the specific file that contains a specific allocation unit.   I've been messing around with %%physloc%% in the hopes it could help, but it doesn't quite get me what I'm seeking. The links below were provided by :    (sqlity.net)  by


Use sed to replace string but avoid replacing when it is a substring

I would like to perform string substitution in several files.  The string is particular as it is in the form  use module_plotting and I need to avoid the replacement when encountering a string like use module_plotting_debug.  Thanks is advance for the answer(s)


Evaluate a limit involving the inverse of a function

Let $f : [1, \infty) \to [1, \infty)$ be a function such that $f(x) = x(1 + \ln x)$. Prove that $f$ is bijective and then calculate: $$\lim_{x \to \infty} \frac{f^{-1}(x) \ln x}{x}$$  I have no difficulties in proving that $f$ is bijective, but I can't calculate the limit. I've tried using l'Hospital's rule but got nothing meaningful.  Thank you in advance!


Is there a way to flag or warn about a review-abuse?

I was reviewing this one:    Though I may admit that this edit was minor... There are two reviewers that classifies that edit as introducing spam, when it's not.  I felt like it was reviewer abuse. I wanted to flag that, but did not find the button.  What is the common way to report that ?  EDIT: well I'm wrong the edit was to be considered spam. Thanks for the answer and downvotes. However you don't answer "what is the common way to report review abuse" ? Simply meta ? The answer can satisfy me, but at least tell it.


Kubuntu 13.10 no sound, missing shutdown button, network disconnected

I just updated to Kubuntu 13.10 and several things are wrong. For instance, the only output sound device is Dummy Output, network icon has a red X on it and shutdown and restart buttons are missing. What is wrong?


Probability that all five objects are connected

Let there be five objects V, W, X, Y, Z. For each pair of objects, a fair coin is tossed. If the coin returns heads, the two objects become connected. If one object is connected to another object, it is connected to every other object the other object is already connected to. What is the probability that all five objects are connected to each other?  I've tried cases with 2, 3 and 4 objects but found no pattern.


biblatex: Retrieve which references are NOT used

I think this is a gerenal issue: If you have a .bib-file with 200 entries and you use maybe about 170 of it, how can you retrieve the missing 30 keys?  The background is: \nocite{*} will add all references, but that's not what I want. I want only the references which are really used. But: I also want to know what keys are not used, so I can scan through that list and check if important references are missing.


What is the purpose of the Assemblies node in Web.Config?

When creating a new ASP.NET AJAX Web Application in Visual Studio 2005, the default web.config contains the following section (inside the compilation node):  <assemblies>     <add assembly="System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"/> </assemblies>   Whether or not the assemblies node exists doesn't seem to affect the AJAX functionality.  Update panels, etc work fine regardless of whether or not the reference to System.Web.Extensions is included in Web.Config.  What's the purpose of this section, and can it be safely removed?


True or false: question about generated ideal and his powers.

Let $R$ be a  commutative ring with identity and $a\in R$. Let $n\in\mathbb{N}$. The principal ideal generated by $a$ is $$\langle{}a\rangle{}=aR=\{ar\;|\;r\in R\}.$$  Question. Is true or false that $\langle{}a\rangle{}^n=\langle{}a^n\rangle{}$?  My attempt It's true for me: in fact by definition $$\langle{}a^n\rangle{}=\{a^nr\;|\;r\in R\},$$ and  $$\langle{}a\rangle{}^n=\bigg\{\sum_{\text{finite}}(a_{1}\cdots a_{n})\;|\;a_i\in\langle{}a\rangle{}\bigg\}=\bigg\{\sum_{\text{finite}}a^n(r_1\cdots\ r_n)\;|\;r_i\in R\bigg\}.$$ We observe that $(a^n)\subseteq(a)^n$, as if $\tilde{a}\in (a^n)$ exists $r\in R$ such that $\tilde{a}=a^nr$, accordingly $\tilde{a}=a^n(r\cdot \underbrace{1_R\cdot 1_R\cdots 1_R}_{n-1\;\text{times}})\in\langle{}a\rangle{}^n$.   Vice versa we prove that $(a^n)\supseteq(a)^n$. If $\overline{a}\in\langle{a}\rangle^n$, then $\overline{a}=\sum_{\text{finite}}\overline{a}^n(t_1\cdots\ t_n)$, where $t_i\in R$. Therefore $\overline{a}=a^n[\underbrace{(s_1\cdots \ s_n)\underbrace{+\cdots+}_{\text{finite}}(v_1\cdots v_n)]}_{:=r}$, then $\overline{a}=a^nr$, where $r\in R$. Therefore $\overline{a}\in\langle{}a\rangle{}^n$.  Thanks!


Why can't the second MAV reach the Hermes?

In the beginning of The Martian, the first MAV can reach orbiting Hermes just fine with 5 passengers on board. Yet towards the end of the movie, we are shown that the second MAV needs to lose weight to do the same, even with only one passenger. Why is this?


Question about the Grover-Sysoev algorithm

We consider  a quantum circuit that takes as input two vectors $\vert x \rangle$  and $\vert y \rangle$. The output of this quantum circuit must contain the reflected vector of   $\vert y \rangle$  with respect to  $\vert x \rangle$  (and whatever else that is irrelevant to the purpose ).  that this operator is nonlinear in the first argument, and in general is not unitary.  So no chances of implementing this operator with a quantum circuit, in complete generality.  However, In the reference linked in my question  it is proved that a deterministic programmable gate array must have as many Hilbert dimensions in the program register as programs are implemented (consequence of the orthogonality requirement of the program states). If each program is given as input on n qubits, then n programs would require the array to have $n^2$ qubits in the program register, but in principle possible. In our case $\vert x \rangle$ is the program, the reflection axis. So we can implement all the operators $U_{\xi_k}$ described below  for $k=1.2.3......n$  And that means that these operators allow an implementation (with one quantum circuit with $n^2$  input "program" qubits ) as long as the program states are orthogonal (as explained above ).   And that means that the  can be implemented. This consists in the following $n$ steps: $$|\xi_1\rangle = U_s U_\omega |s\rangle, \quad \vert \xi_2 \rangle = U_{\xi_1} U_\omega \vert s \rangle, \quad \cdots \quad  \vert \xi_n \rangle = U_{\xi_{n-1}} U_\omega \vert  s \rangle, $$ where $U_\omega\equiv I - 2  (\vert\omega\rangle\langle\omega \vert )$ and $U_s \equiv 2\vert s \rangle \langle s \vert - I$.  This algorithm finds a solution exponentially faster than Grover's. In other words, for a fixed large $n$ we can actually build this complex quantum circuit that would solve problems of practical interest efficiently.  The difference between this and the original Grover algorithm is that we perform an inversion about the previous state vector of the algorithm, rather than about the mean, at each step.  Note that the optimality proof in Grover 's original paper doesn't include operators with "program"  registers as input.   Question  1. Is this algorithm  possible to implement,  in principle?  Question 2. Is this algorithm exponentially faster that Grover, for a fixed, chosen n?  The way "exponentially faster" is defined implies considering arbitrarily large values of n,  but the meaning of this question is clear from the context.   My calculations indicate that both questions allow "yes" answers, but I could be wrong.   Another related question I asked previously can be found .


Which is correct.  Dan thought it would make sense for me and Val to attend training.  OR Dan thought it would make sense for Val and I to attend training.


Performing multiple layer intersection in QGIS?

I am trying to find a way with QGIS to get the intersection area of more than 2 layers.  All the tools in QGIS take just the 2 input layers.  For example in the image below, I have 4 layers and I want to retrieve just the black area.   Furthermore, I need to retrieve the count attribute and add it to the intersected area attribute table (in this case 4)    I know there is a tool that does the trick in ArcGIS, but is there a QGIS solution?


Which one is correct, "brothers" or "brethren"?

I read a text in which "brethren" was used instead of "brothers". Is that common to use or it is an older plural form for "brother"?


The equivalent electric field of a magnetic field

I know that Lorentz force for a charge $q$, with velocity $\vec{v}$ in magnetic field $\vec{B}$ is given by  $$\vec{F} =q \vec{v} \times \vec{B}$$  but there will exist a frame of reference where observer move at same velocity with that of charge $q$, so according to him $v=0$. hence he will see no magnetic force is exerted on charge $q$. I have work on this problem for a while and found that the special relativity predicts equivalent electric force will acting upon charge instead. I want to know the relationship between this equivalent electric force and magnetic force.  Thanks in advance


Prove that the interval $(0, 1)$ and the Cartesian product $(0, 1) \times (0, 1)$ have the same cardinality  using the SB theorem? Also how does one find a bijection on $f:(0, \infty) \to (0,1)$ such that they have the same cardiniality?


Guidelines for posting Apple-related questions on [[Ask Different]] versus [[Super User]]

There seems to be substantial overlap in the respective question domains of Ask Different and Super User, as the latter contains thousands of Apple-specific questions. What are the rules, guidelines, or etiquette for determining which site is more appropriate for a given Apple-related question?  (I gather that cross-posting is not allowed.)


how do i dividing the sentence into a word

how do i divide a sentences in c++ like :  input from cin  (He said, "that's not a good idea". )  into  He Said That s not a good idea  to test whether a character is a letter, use a statement (ch >='a' && ch <='z') || (ch >='A' && ch <='Z').


Recovering files from old internal disk without windows authentication

So I have an old hard drive which ran Windows XP. The rest of the computer was scraped. I can't recall the login password for the user on that hard drive. I want to recover files from this hard drive.  My question:  If I get an adapter and connect it to my PC running windows 10 will I be able to simply access the drive as if it was a new drive and browse the files? If not how do I retrieve the files?  Also if I want to completely copy the content of the disk to a new hard drive can achieve that with a tool like deamon?


Object appears twice when linking it to a collection

I am creating a bone, and then a collection with a specific name if it does not exist, with the following function: def make_collection(collection_name):     if collection_name in bpy.data.collections:         return bpy.data.collections[collection_name]     else:         new_collection = bpy.data.collections.new(collection_name)         bpy.context.scene.collection.children.link(new_collection)         return new_collection  The collection is linked to the master collection so it's on the top of the hierarchy, and now i try link it to the collection. I create the collection: root = make_collection("bat")  and later on in the code, i create a bone (although is an empty since it's a standalone bone), and i try to link it like this: bpy.ops.object.empty_add(type='CUBE') bone = bpy.context.active_object bone.name = data[i].name #bpy.ops.collection.objects_add_active(collection=root) root.objects.link(bone)  Even though it's called root, root is not the master collection, just to clarify. The result is the following:  It's the same empty i created, that appears twice in both collections. Although an idea would be to just delete other collections, 2 will appear still, one in the master collection, and one in the collection i created. Also it's the same item since, if i click one, both get selected at the same time, so there's only one empty in the scene, i just can choose where to click it from. Now the problem is i'm doing this with several objects in a loop, so i  would be basically duplicating the object list twice, and that's pretty redundant. If i don't use the root.objects.link code at all, the objects would just be on the master collection, but i want them to be on the collection i specifically created. Is there any way to fix this? I'm not sure why it appears on both collections and i'm very confused. I'm fairly new with the blender API, so i'm not sure what i'm doing wrong. Thanks for reading!


What is the difference between `Area_2D`, `Area_3D`, and `Volume` in surface volume calculation?

I want to know the meaning of output text files of surface volume dialog box. For example, the file contains headers and numbers as below:  Dataset, Plane_Height, Reference, Z_Factor, Area_2D, Area_3D, Volume.  raster_to_tin, 50,00, BELOW, 1,000000, 385387,1505728, 414338,45311207, 4544086,3828428   What is the difference between Area_2D, Area_3D, and Volume?


Can set of integers form a vector space over field of rationals?

As field of reals $\mathbb{R}$ can be made  a vector space over field of complex numbers $\mathbb{C}$ but not in the usual way. In the same way can we make the ring of integers $\mathbb{Z}$ as a vector space the field of rationals $\mathbb{Q}$? It is clear if it forms a vector space, then $\dim_{\mathbb{Q}}\mathbb{Z}$ will be finite. Now i am stuck. Please help me. Thanks in advance.


How do you answer tag questions with ", right?"?

When you asked "You don't love me, right?":  Which word is used to answer, "Right." or "Yes."?   If the answer is "Right":   --> Does "Right" mean "What you said is right, i.e., I don't love you.", doesn't it?  If the answer is "Yes":   --> Which does "Yes" mean, "Yes, what you said is right." or "Yes, I love you."?


Travelling to Himalayan National Park or Nanda Devi Reserve in Monsoon

I will be arriving to New Delhi in 15th August and this is a rainy time in Delhi as well as certain other parts in northern India.  Is it safe to travel to any one of these two national parks in the Monsoon season? Are there any additional precautions which I should take while doing the same?


Boy at relative's house, pill makes him immune to mold-like monster

So around 20 years ago I read a book and hope to find it again. I have very slight memory of what happened except one scene. This will be paraphrased.  A young boy is at a relatives house. The house goes dark and he gets a flashlight from on top of the fridge. He finds a pill on the table and takes it. Then there is a mold like monster that tries to get him but the pill made him immune to it.  That's all I can remember.


Is there any evolutionary/physiological advantage to multi-lateral symmetry?

Just wondering ; I get the impression a large number of multicellular organisms are multi-lateral in their physical structure. Why would evolution/mutation have retained multi-lateral symmetry in an organism? What advantage/s does symmetry provide an organism?  EDIT:  By multi-lateral symmetry I mean at-least bi-lateral symmetry (as in the case of many beings such as elephants, crabs and fishes), but perhaps more than bi-lateral too (starfish come to mind)  END EDIT:


I am working through the following tutorial about how to create clusters within a dataset. .  Using the following code, we can create a plot where we visualise the three clusters which have been formed.  library(factoextra) library(cluster) library(NbClust) # data(iris) head(iris) # iris.scaled <- scale(iris[, -5]) head(iris.scaled) # # K-means clustering set.seed(123) km.res <- kmeans(iris.scaled, 3, nstart = 25)   # # lets inspect the output here kmeans(iris.scaled, 3, nstart = 25) # #   # k-means group number of each observation km.res$cluster # # Visualize k-means clusters fviz_cluster(km.res, data = iris.scaled, geom = "point",              stand = FALSE, frame.type = "norm") + theme_bw()   While, it looks fantastic that we have found three clusters within the dataset, I cannot understand what we have plotted on our x and y axis, what is the Dim1 and Dim2 and what does the 73 and 22.9% have to do with anything.  We plot the output from the kmeans command, where I assume it calls upon the Cluster means:??


How to remove the logo from a Tkinter window?

I create a python window (Tkinter) and I want to remove an icon from it and add new icon to python window.


7zip on several terabytes, drive already compressed

so, I have a drive that is NTFS. it has thousands of graphics/video files that totals to about 6TB. I wanted to compress and send this info to someone.  What is my best option for compressing? I've also noticed that the drive has compression set on file explorer: "compress this drive to save disk space"  When I start to use 7zip on the data, the total is larger than what I anticipated, like 8TB or 9TB which I'm guessing is because drive compression is on.  I've tried Keka on mac but it's going slow as hell. What are my options here to ensure the recipient doesn't get corrupted data? Currently, I'm trying using 7zip format and 'store' for compression. Thanks!


Consider the set $V$ of upper-triangular $n\times n$ matrices with elements in some ﬁeld $K$. I.e., if $A$ is such a matrix, $a_{ij} = 0$, for $i > j$  Show that non-degenerate upper-triangular matrices form a group with respect to matrix multiplication.


Case-insensitive string comparison without using lower or upper

I am trying to compare two string and ignore case- sensitive but i don't want to use .lower() or .upper(). Is there another way of doing this?


How to add a shortcut for changing keyboard language ubuntu 18.04?

I'm new to Ubuntu I want to now how I can add a shortcut like alt+shift in windows to change the keyboard language  thank you


How to check if code running is run directly via file or run via importing in some other file in python?

I am trying to make a CLI and GUI for a appliaction in which I am using my CLI to perform task and return string for my GUI and give output.  But problem is when I import my CLI it first takes input as it should when it is run from direct CLI, but I do not want it to take input from CLI when running from GUI.  So, for this is there any way from which I can check if the CLI script is run directly or from CLI or is imported in some file and then being run.  this is an example what I did:  cli.py  print("hello CLI run") x=input() def pr(x):     return("this is what you typed = "+x) print(pr(x))   gui.py  from tkinter import * from cli import pr def sb():     c=en.get()     zz=pr(c)     expression.insert(0,zz) win=Tk() lbl=Label(win,text="Hello World") lbl.pack() en=Entry(win) en.pack() sn=Button(win,height = 2, width = 10,text="submit",command=sb) sn.pack() lbl=Label(win,text="Output :") lbl.pack() expression=Entry(win) expression.pack() win.mainloop()   When I run this this asks me to input in CLI first and then give CLI output and then run the GUI


While it's possible to get links to questions and comments that include the title of the question in the link, I haven't seen a way to do this for answers.  Question link:   Answer link:   Comment link:   When commenting code about a particular solution used, I sometimes prefer to link to an answer rather than the question. However I miss the descriptiveness of the overall question link url.  Edit: There is a feature request part to this question. While it possible to click on the title of a question or the time stamp of a comment to get sent to a link, there is no such direct feature for answers. As the  to this question suggested, the only way to do so, is to paste and go to the shortlink. Surely if there was a place to click a link for answers, as there is with questions and comments, there might not be a question on , with 171 upvotes


How do I join two worksheets in Excel as I would in SQL?

I have two worksheets in two different Excel files. They both contain a list of names, id numbers, and associated data. One is a master list that includes general demographic fields, and the other is a list that only includes name and id, and an address. This list was pared down from the master list by another office.  I want to use the 2nd list to filter the first. Additionally, I want the results to include other fields from the master worksheet alongside the address fields from the second worksheet. I know how I could do this very easily with a database inner join, but I'm less clear on how to do this efficiently in Excel. How can join two worksheets in Excel? Bonus points for showing how to do outer joins as well, and I would greatly prefer knowing how to do this without needing a macro.


How can I combine multiple rows into a comma-delimited list in Oracle?

I have a simple query:  select * from countries   with the following results:  country_name ------------ Albania Andorra Antigua .....   I would like to return the results in one row, so like this:  Albania, Andorra, Antigua, ...   Of course, I can write a PL/SQL function to do the job (I already did in Oracle 10g), but is there a nicer, preferably non-Oracle-specific solution (or may be a built-in function) for this task?  I would generally use it to avoid multiple rows in a sub-query, so if a person has more then one citizenship, I do not want her/him to be a duplicate in the list.  My question is based on the similar question on .  UPDATE: My function looks like this:  CREATE OR REPLACE FUNCTION APPEND_FIELD (sqlstr in varchar2, sep in varchar2 ) return varchar2 is ret varchar2(4000) := ''; TYPE cur_typ IS REF CURSOR; rec cur_typ; field varchar2(4000); begin      OPEN rec FOR sqlstr;      LOOP          FETCH rec INTO field;          EXIT WHEN rec%NOTFOUND;          ret := ret || field || sep;      END LOOP;      if length(ret) = 0 then           RETURN '';      else           RETURN substr(ret,1,length(ret)-length(sep));      end if; end;


how to install 32bit support in Ubuntu 16.04 64bit?

sudo apt-add-architecture i386   The above command does not work in Ubuntu 16.04 64bit I need 32bit support, how can I do?


Company policy won't let me install LaTeX. Is there a way to create a standalone .exe?

My company has very restrictive IT policies. I am not allowed to install LaTeX and the company rules won't let IT install anything that doesn't appear on their list of safe software. I think I see a safe and legal workaround though. I have an application for viewing videos that can produce standalone executables. These standalone executables allow someone without admin rights to use a limited version of the video software just by placing the .exe file on their computer and opening it.  Has anyone created something similiar for LaTeX? Does anyone have any ideas for a good workaround? (Safe and legal)


I would like to ask something. Is it possible to change my android phone to ubuntu??? like to change the rom or anythink it needs to be full ubuntu.  I have galaxy s4 gt-i9505.


If $\,A^k=0$ and $AB=BA$, then $\,\det(A+B)=\det B$

Assume that the matrices $A,\: B\in \mathbb{R}^{n\times n}$ satisfy  $$ A^k=0,\,\, \text{for some $\,k\in \mathbb{Z^+}$}\quad\text{and}\quad AB=BA. $$  Prove that $$\det(A+B)=\det B.$$


in my code please help i keep getting : Exception in thread "main" java.lang.NullPointerException

package Josh_the_bot;  /**  *  * @author Jarvis-Main  */ import java.util.*; import javax.swing.JOptionPane; public class Josh_the_bot {      /**      * @param args the command line arguments      * @throws java.lang.InterruptedException      */     public static void main(String[] args) throws InterruptedException {         // TODO code application logic here          Scanner namea = new Scanner (System.in);         int temperature = 0 ;         String theName;         theName = "Josh";         String name = JOptionPane.showInputDialog("Hello What Is Your Name?");         int namez = Integer.getInteger(name);         String namereply = JOptionPane.showInputDialog( "O hello" + namez );         int lel = Integer.parseInt(namereply);   I get this error  Exception in thread "main" java.lang.NullPointerException at Josh_the_bot.Josh_the_bot.main(Josh_the_bot.java:27)   Java Result: 1


This isn’t a duplicate. I read those pages, but those didn’t answer my questions.  Please watch .  Does visible light consist of red, orange, yellow, green, cyan and blue? No purple? My definition of purple has an RGB of 128, 0, 128:    If there’s purple in visible light, visible light and a rainbow are different since there’s no purple in a rainbow. If there’s purple in visible light, what’s the explanation behind the difference between a rainbow and visible light?


Has it been shown that consuming less than 1000 mg of calcium per day is harmful?

The RDI for calcium is 1000-1300 mg. I wonder if it was established simply by observing what normal healthy people consume daily, or has it actually been shown that consuming only, say, 500 mg is bad for you?


Can I automatically add a guest user (guest-session) to a user group? How can I do it)

I need guest users to be in a specific user group. I probably could create a new guest-account and add it to the group. But I'd rather like to use the existing guest-session-option integrated in Ubuntu (16.04). Is there any way to do it? I only found ways to automaticaly launch scripts/programs or costumize the startup-dialog. Thank you very much in advance!


As we know, $2^{\aleph_0}$ is a cardinal number, so it is a limit ordinal number. However, it must not be $2^\omega$, since $2^\omega=\sup\{2^\alpha|\alpha<\omega\}=\omega=\aleph_0<2^{\aleph_0}$, and even not be $\sum_{i = n<\omega}^{0}\omega^i\cdot a_i$ where $\forall i \le n[a_i \in \omega]$. Since $\|\sum_{i = n<\omega}^{0}\omega^i\cdot a_i\| \le \aleph_0$ for all of them.  Besides, $\sup\{\sum_{i = n<\omega}^{0}\omega^i\cdot a_i|\forall i \le n(a_i \in \omega)\}=\omega^\omega$, and $\|\omega^\omega\|=2^{\aleph_0}$ since every element in there can be wrote as $\sum_{i = n<\omega}^{0}\omega^i\cdot a_i$ where $\forall i \le n[a_i \in \omega]$ and actually $\aleph_{0}^{\aleph_0}=2^{\aleph_0}$ many.   Therefore $\omega^\omega$ is the least ordinal number such that has cardinality $2^{\aleph_0}$, and all ordinal numbers below it has at most cardinality $\aleph_0$. Hence $\omega^\omega=2^{\aleph_0}=\aleph_1$?


How many subgroups of order 8 of an abelian group of order 72?

In Fraleigh, there is a question asking if you can say how many subgroups of order 8 an abelian group $G$ of order 72 has, and also if you can say how many subgroups of order 4 that group has. The answer key says there is only one of order 8, but I don't understand why.   I know that $G$ can be decomposed into a direct product of cyclic groups. But both $Z_8 \times Z_9$ and $ Z_2  \times Z_4 \times Z_9$ are of order 72; while the first one has a subgroup $Z_8$, the second one has a subgroup of $Z_2 \times Z_4$, and these two groups are not isomorphic.  What am I missing? Also, why couldn't we say how many groups of order 4 $G$ has?


Concentration and manipulation of magnetic fields

is it possible to concentrate magnetic fields, via concave electric coils? If a current is induced in such as a concave cylinder shaped coil.


What is the list of commands to dictate punctuation, capitalization and line breaks?

I'm on a Sprint Samsung Galaxy S3 with Android 4.3.  I would love to become a power user of the dictation feature to dictate text messages and emails. More often than not, however, I have to hand-edit the dictated text not because of text comprehension issues but because of punctuation, capitalization and spacing problems.  These are the "commands" I've found to work. What is the full list?  "period"     --> .   (works fairly reliably) "comma"      --> ,   (works fairly reliably) "new line"   --> \n  (works about 50% of the time)   I've not gotten capital or anything like that to work, or acronyms. If you know how it works, please share.


Why does fwrite write two bytes for an uint8_t?

Not very skilled in C. This might be just a newbie question.  I am trying to write 3 bytes to file, but end up with 4.   #include <stdio.h> #include <stdlib.h>  struct a {   uint8_t x;   uint16_t y; };  int main() {   struct a record = { 1, 2 };   FILE *fp = fopen("example.bin", "w");   fwrite(&record, sizeof(struct a), 1, fp);   fclose(fp); }   For some reason I end up with:  $ hexdump -C example.bin 00000000  01 00 02 00                                       |....| 00000004   I was expecting: 01 02 00.  Here is the version of my c compiler in case this is hardware/compiler related.  $ cc --version Apple LLVM version 9.1.0 (clang-902.0.39.1) Target: x86_64-apple-darwin17.5.0 Thread model: posix


Word for a person who continually tries to teach you when it's not necessary

I've experienced this way too many times, and the best example I can give is a person who treats you like you have no idea how to do X and who keeps teaching you how to do it. I feel handicapped. Take for example how to play a card game. You know how to play the game because you've played it 5 times. However, there is a person always insists on explaining the game to you - like you are always new to the game - when you don't actually need any help and you just want to think for yourself. Another example situation is doing a repetitive task which you already have experience with, and yet the person continually tries to 'teach' you when you don't need help/already know how to do it. It almost makes you mad because you really don't need help. As an example which recently happened to me:  "Hey, do you remember how to start the wood chipper?" "Yes I do" "Okay, well, let me show you one more time"  Again, is there a term for someone who does this?


Short story collection: starts out with alien talking about his giant ship they built

Their planet is dying or something and they all go in different directions, and he crash-lands on Earth on a farm I think. His ship is about the size of a bowling ball to us, and he's the size of an insect. He's exploring the area when a human picks him up, and he uses his laser on the human but the human just thinks it's a bug bite and squashes him. I think it was like he was writing in a "captain's log" sort of thing. It was a paperback, I can't remember if it was the first story of the collection but I think it was more in the middle of the book, and I thought they were all the same author but now I'm not sure. I thought it was Asimov but now I'm not sure.


Difference between '[:]' and '[::]' slicing when copying a list?

We can (shallow) copy a list by using [:]:  l = [1, 2, 3] z1 = l[:]   We can also (shallow) copy it by using [::]:  z2 = l[::]   and now z1 == z2 will be True. I understand how these slices work after reading the answers in .  But, my question is, is there any difference between these two internally? Is one more efficient than the other in copying or do they do exactly the same things?


Serializing and Deserializing Expression Trees in C#

Is there a way to Deserialize Expressions in C#, I would like to store Expressions in a Database and load them at run time.


Naruto's father's name is Minato Namikaze, and mother is Kushina Uzumaki. So, why is Naruto's surname Uzumaki? Shoudn't it be Namikaze?


Am not talking about drop down menu indicators , I need a classic menu i can place it at the unity launcher so it will be a good navigator with a lot of tools .


Multiple I2C devices with the same address

I have multiple devices with the same address, and only one I2C bus. If I don't want to/can't use an address multiplexer, will the following arrangement work? (sorry for the messy schematic)          – Schematic created using   SW1 and SW2 are microcontroller I/O, and are pulled low when we don't want to talk to the corresponding IC, and set to high impedance when we do want to talk to that IC. Can anyone see any problems with this, apart from with clock stretching? Assuming you choose diodes with a small voltage drop, like a schottky.  Edit:   Also assuming that the VIH and VIL all worked out with the diode drop and the VOH VOL.   The diodes could also go on the data lines instead, not sure if there would be any benefit/difference (maybe some I2C devices do something special when the clock goes low even if it's not their address? It's probably safer to not clock at all i.e. have the diodes on the clock lines.


Optimum Dimensions of a Closed Cylindrical Can

I was doing math for time-killing, and I stumbled upon this question:  "Find the most economical dimensions for a closed cylindrical can containing a quart."  My work:  I do know that the volume $V$of cylinder is $V = \pi r^2h.$ I applied differentiation like this:$$d(V) = d(\pi r^2h) $$ Then: $$dV = \pi r^2 + 2\pi rh.$$ I set the $dV$ to be zero to get the optimum dimensions: $$0 = \pi r^2 + 2\pi rh$$ $$-\pi r^2 = 2\pi rh$$ $$-r=2h$$  The solution I got seems legitimate because I would just ignore the negative sign, getting the dimensions the radius must equal to twice of the cylinder's height.   And that's one fat can we got. In the book I used the answer is the dimensions must be Diameter = Height.  How do you get the optimum dimensions Diameter = Height?


How to toggle spell checking quickly in Microsoft Word

It would help if there is a way to toggle the underlining on and off programmatically, assigning the command to a button to enable me to toggle with a single click.  It is a pain to go through the menus every time I want to do it currently.  How do I do this?


Where are crontab -e settings saved in ubuntu 16.04? Working, but can't find

I created a cron job by invoking:  # crontab -e   but I can't find the file with my edits.    Here's the /etc/crontab file:  # m h dom mon dow user  command  117 *    * * *   root    cd / && run-parts --report /etc/cron.hourly1  25 6    * * *   root    test -x /usr/sbin/anacron || ( cd / && run-parts --repo$ 47 6    * * 7   root    test -x /usr/sbin/anacron || ( cd / && run-parts --repo$  52 6    1 * *   root    test -x /usr/sbin/anacron || ( cd / && run-parts --repo$   crontab -e shows   */2 * * * * /home/avery/Dropbox/Scripts/lftp_download.sh   Anybody know which file my edits might be? I've looked at most the cron-related files in /etc but I can't find the one that's loaded when I type crontab -e.  Also, is there a log file in Ubuntu for cron?  Thanks in advance, Avery


Why aren't the graphs of $\sin(\arcsin x)$ and $\arcsin(\sin x)$ the same?

()    ()  Both functions simplify to x, but why aren't the graphs the same?


Unable to authenticate iMessage on MBP, but working on iPhone/iPad

Yesterday, I tried to send a text through iMessage on my MBP 13" (2020) only find it not sent about 10 minutes later. I tried sending it again, the same outcome. I sent the message directly through my iPhone SE (2020) without any problems. Fact: text service is working fine. I decided to logout/login to iCloud on my MBP. This of course necessitated me to reconnect my iPhone and iPad to my iCloud account. Those reconnect without any problem. The problem came with the MBP. iMessage asks me to log in with my Apple ID and I get the following error message:   Could not sign in to iMessage. An error occurred during activation. Try again.  I have tried multiple times to connect/authenticate iMessage without success. I am wondering if a preference file has been corrupted and is unable to authenticate. How can I fix this error and reconnect iMessage to iCloud? MBP 13" (2020): running 10.15.6


Windows 8 Task Manager RAM Usage Accuracy

The new Task Manager has a great UI in windows 8, however, there are some discrepancies in the data I can not account for:  Machine: 8 GB of total ram. (This is a physical machine, not a virtual)  The processes tab shows 45% of Memory utilized.  The listed process do not add up to 3.5 GB of RAM, but instead add up to 0.948 GB. There is no "processes for all users" option.   The performance Tab Shows:   In use : 3.6 GB Available: 4.4 GB Committed : 4.1 /9.2 GB  Cached: 3.7 GB Paged Pool: 376 MB Non-paged pool: 135 MB  My reading of this says I have ALOT of "cloaked" processes running some where eating my ram.  How do I interpret this data and how do I verify it?


Which website to ask questions about program environment?

Where should I ask a question that has to do with "working your way around a program"?  Here's the question:     I have 2 monitors (they are different sizes). I'm trying to view and   edit the code (HTML, css, JavaScript) in one screen, and have the   live/preview window at the second screen. There doesn't seem to be an   easy way to do this. Do you have any suggestions?


What do the groups do in "Users and Groups"?

I know that some define permissions on the file system (such as www-data).  But I don't understand why  by adding a user to the "Video" group.  So the question is mainly what do all the pre-built groups do in Ubuntu?  More reasonably, since there are so many, what "special" groups exist and how or when should they be used?


What's the difference between double quotes and single quote in C#?  I coded a program to count how many words are in a file  using System; using System.IO; namespace Consoleapp05 {     class Program     {         public static void Main(string[] args)         {             StreamReader sr = new StreamReader(@"C:\words.txt");             string text = sr.ReadToEnd();             int howmany = 0;             int howmany2 = 0;              for(int i = 0; i < text.Length; i++)             {                 if(text[i] == " ")                 {                 howmany++;                 }             }             howmany2 = howmany + 1;             Console.WriteLine("It is {0} words in the file", howmany2);             Console.ReadKey(true);         }     } }   This gives me an error because of the double quotes. My teacher told me to use single quote instead, but he didn't tell me why. So what's the difference between double quotes and single quote in C#?


How to promote the "include script with your question" to newcomers

Many of the questions, in Stack Overflow, I have seen the new users are not posting part of there script with their question or they fail to post their attempt at getting the script working  How can it be promoted for users to post their script for the rest of us to comment / work on to get a working peace of script?  Maybe have it as part of the Question submitting page?


I want to know a few things   Has anyone tried Unity 8 on 16.04 ? How buggy is it ? What are to commands to use it on 16.04 ? My PC has Virtualbox installed. Heard Mir does not support it (?) Will I have to install something else to try Unity 8 on 16.04 ?   Thanks.


Can a husband and wife combine their UK Standard Visitor visa applications?

We applied for UK Standard Visitor visas as two separate applications.  After completing our biometrics do we need to send the applications with supporting documents as two separate postal mails for stamping or can we send it as one?  Also does the return label have to be two different prepaid return shipping labels or is one enough?


M is finitely generated but $\ker(f)\subset M$ is not.

So I'm searching for an homomorphism of $A$-modules $f:M\mapsto N $ and some A-modules $M$, $N$ such both are finitely generated but $\ker f\subset M$ is not.  Thanks.


Run the cron jobs based on specific conditions using spring boot.What is wrong in below mentioned java code

I am trying to run the cron jobs based on specific conditions using spring boot. Ex: if(bankName=="Sbi") then run the sbi job scheduler, if(bankName =="City") then run the city job scheduler and so on.  I am getting bank name through the database (service which fetch the bank details by customer account number) and I am not able to run the job based on the specified condition.  I am expecting output as bank name is 'sbi' then run task1 job and bank name is 'city' then run task2 job. But it run task3 job(bank name is 'hdfc') also even the if condition not met.  Please find below code snippet.  Note: I have put the break-point in SchedulingTask.java file for debugging purpose but it seems not hitting this break point. Please guide me how I can fix this problem.       @SpringBootApplication             @EnableScheduling             public class SpringBootApp {                 public static void main(String[] args) {                      SpringApplication.run(SpringBootApp.class, args);                     // new SchedulingTask();                 }             }              @Configuration             @EnableScheduling             public class SchedulingTask {             /* I have to get the Bankname from database  for testing i am hard-coding the name*/                     String [] bankName = {"Sbi","City"};                              void  foo(String[] bankName) {                         for (String name : bankName) {                             setBankName(name);                         }                            }                  public  void setBankName(String name) {                     if(name.equalsIgnoreCase("sbi")) {                           new Task1();                     }                      else if(name.equalsIgnoreCase("City")) {                                 new Task2();                     }                      else if(name.equalsIgnoreCase("Hdfc")) {                                  new Task3();                     }                 }                }  @Configuration @EnableScheduling public class Task1 {      @Bean     @ConditionalOnProperty(value = "Sbi", matchIfMissing = true, havingValue = "true")     public SchedulingTask1 scheduledSbiJob() {         return new SchedulingTask1();     }  }  @Configuration @EnableScheduling public class Task2 {      @Bean     @ConditionalOnProperty(value = "City", matchIfMissing = true, havingValue = "true")     public SchedulingTask2 scheduledCityJob() {         return new SchedulingTask2();     }  }  @Configuration @EnableScheduling public class Task3 {      @Bean     @ConditionalOnProperty(value = "Hdfc", matchIfMissing = true, havingValue = "true")     public SchedulingTask3 scheduledHdfcJob() {         return new SchedulingTask3();     }  }  @Component public class SchedulingTask1 {     @Scheduled(cron="*/2 * * * * ?")     public void sbiTask() {         System.out.println("sbiTask method excuted at every 2 seconds.  Current time is :: " +new Date());     } }  @Component public class SchedulingTask2 {     @Scheduled(cron="*/4 * * * * ?")     public void cityTask() {         System.out.println("cityTask method excuted at every 4 seconds.  Current time is :: " +new Date());     } }  @Component public class SchedulingTask3 {     @Scheduled(cron="*/6 * * * * ?")     public void hdfcTask() {         System.out.println("hdfcTask method excuted at every 6 seconds.  Current time is :: " +new Date());     } }


Restore deleted Mysql Directory in linux

My MySQL directory has been deleted from  directory /root/var/ by mistake, we need to restore it, Is it possible ?


How do I log in to Hotmail instead of Outlook.com?

I have been trying to log in to my Hotmail account and I can't because Outlook.com keeps coming up instead. Is there any way that I can still log in to Hotmail?


How do I install Google Play on Cyanogen Mod 10.1?

I see CyanogenMod 10.1 removed Rom Manager. How do I now install Google Play?


Script to Output Tables to CSV Showing Heading Only Once

I am trying to write a script that will output a table to a CSV.  The tricky part has been to get the output to only show the header once.  The script below does not show the header at all.  The other option we have used is is setting the pagesize extremely high.  That has also been very problematic.  set colsep | set pagesize 0 set trimspool on set linesize 10000   spool table1.csv SELECT host_name from v$instance; select to_char(sysdate, 'Dy DD-Mon-YYYY HH24:MI:SS') as "CURRENT TIME" from dual; prompt ================================================ prompt    TABLE 1 prompt    SELECT * FROM tbl1; prompt ================================================ SELECT * FROM tbl1; spool off   For clarity: I do not have direct access to the database.  I will be passing the script to a DBA to run against the database, so PL/SQL or anything else more advanced than a very basic script is probably not an option.  Also because of this, I want the column headers to show ONCE and only once whether there are 10 or 10 million records in the table.  This will give me reasonable descriptions of data that I need and minimize the cleanup before analyzing the data.


approximation symbol with a letter under it

How to write the (approximation iniquity) with a letter under it on latex?


8 A Letters in Boxes next to OS X Logo in Overview Panel

When I opened Mac OS X overview panel to check out how much storage I have left, I saw this strange thing. It doesn't affect the performance by any means, but it is not aesthetically pleasing. How can I get rid of it?


Calculate x-coord from given y-coord in data table


Term for self-serving behavior disguised as altruism?

Once when I was having a hard time a guy said to me, "I'm sorry you're having a hard time, I'll pray for you," in a way that made it clear that he was glad I was having a hard time because it gave him the opportunity to pray for me and feel good about himself.   I am interested in this phenomenon but also the much more general (probably universal) phenomenon of human beings finding justification for things they want to do, often by lying to themselves about the utility of the behavior to other people.  The best single word I can think of for this is contrived, but it is not close to precise. Similarly, dissembling, insincere, and so on don't really cut it.   I also looked at this  but was unable to find one that expressed this idea.   Is there a single word for this? If not, a short phrase?


An algebra is a collection of subsets closed under finite unions and intersections. A sigma algebra is a collection closed under countable unions and intersections.   Whats the difference between finite and countable unions and intersections? Does "countable" mean it implies there can be infinitely many unions and intersections?    Secondly, I was reading a definition  For an algebra on a set: By De Morgan's law, $A \cap B = (A^c \cup B^c)^c$, thus an algebra is a collection of subsets closed under finite unions and intersections.  What law are they using here to get $A \cap B = (A^c \cup B^c)^c$? I thought de morgan's law was $(A\cap B)^c = A^c \cup B^c$?  Finally, what exactly do they mean by "closed under finite unions and intersections?


Delay in approval leads to missing out on being awarded an "Explainer" badge

I am not sure if this is a bug or a design error, but I came across this issue on Robotics. I assume that the same code is employed across the various SE sites, so I am posting my question here. I submitted an answer to  at 16:26.    I then suggested an edit to the question at 17:03. However, it was not until 20 hours later, at 13:03, that the edit was approved, so I appear to have missed out on the "Explainer" badge, as the edit should be done within 12 hours.    I don't know the reason for the delay, as I do not have a low approval rating:    I'm not bothered about missing out on the badge, nor am I criticising the reviewers - after all, we all do this in our free time. However, it does seem that the algorithm for the badge relies on the approval time, in lieu of the submit time, which does not seem to be correct, as the badge then becomes dependant upon the reviewer's availability/responsiveness, rather than upon the actions of the answerer/editor.  TL;DR Should the badge also check if the edit was caused by a suggested edit and, in those cases, look at the time it was suggested rather than the time it was eventually approved?


I want to rename all the files in a folder with PREFIX+COUNTER+FILENAME  for ex.  input:   england.txt   canada.txt   france.txt   output:    CO_01_england.txt   CO_02_canada.txt   CO_03_france.txt


Proving the countability of a set of polynomials

I want to show that the set of all polynomials with rational coefficients is countable.   I know that to prove this I need to find a mapping $f$ from the natural numbers to this set that is a bijection. But I'm struggling conceptually of how to think of this. In fact, my intuition is that this isn't even true since can't we plug in an uncountable set of numbers into our polynomial? It's because of this thought that I can't even think of what a bijection would be like. If anyone could help untangle these conceptual issues I'm having that would be good -- I don't necessarily need a proof of the claim, though that's fine too.  Edit: not really a duplicate.


C++ function to check overflow during multiplication does not work when optmizations other than O0 are used

I wrote some code to find whether the multiplication of two integers will result in overflow or not. And can the result be stored as an integer or not?  I am using the GNU GCC compiler and when I compile and run the following code it works but when I use any optimization like O1, O3, etc it does not work.  #include <iostream>    bool mul_overflows(int a,int b)  {     cout<<"checking overflow for"<<a<<" "<<b<<endl;     if(a==0 || b==0)     {       return false;     }     int result = a*b;     cout<<"result = "<<result<<endl;     cout<<"result/b = "<<(result/b)<<endl;     if(a==result/b)       return false;     return true;  }  int main()  {     if(mul_overflows(253955520,12)       cout<<"caught overflow!"<<endl;  }  Following is the output of code with default optimization -O0 checking overflow for 253955520 12 result = -1247501056 result/b = -103958421 caught overflow!  And when I use any other optimization it gives this output checking overflow for253955520 12 result = -1247501056 result/b = 253955520  The overflow is not caught and we can clearly see that the result is negative and has overflowed, but still dividing the result by b gives a? What is causing this? Are there any compiler options that I am missing?


Im looking for a tron AI algorithm on snap!/scratch. If not can you help me develop an AI for this game?


Which method for generating GUID's is best for ensuring the GUID is really unique?

I have been using this for a long long time, but I couldn't find clear explanation on when it is not guaranteed unique. Here are my comments, please correct as you see fit.  Value is guaranteed to be unique(ly created) on the machine it is created. So GUIDs generated by .net app on a machine will never conflict with those that are created by SQL Server on the same machine.  In all other cases there is no guarantee. Theoretically it is always possible that if there are multiple creation sources(say applications on different computers) for the unique identifier field in a db on a different computer, there can be duplicates that'll be inserted.   EDIT: Apologies for not forming the question properly. I guess I wanted to know the probability of conflicts when generated on the same machine vs different machines, if c#'s Guid.NewGuid(), SQL Server's newid(),newsequentialid() functions or any other functions by different applications are used. The 'already answered' link has one of the replies where it says he actually encountered a case where that happened. Makes you wonder how frequently that can happen.   If I have a table with a uniqueidentifier field as the pk, should I have to worry about checking for uniqueness each time I do an insert by creating a new value either by different apps or SQL Server's functions?


Every tag has its questions that make the same mistake(s) over and over and over again. (But some tags more than others.) That's where Benjol's  comes in. The only downside to this great script is that it uses local storage, so if you switch browsers or machine, you lose your data! The team  in incorporating it into the core (at least not at the moment) so  this question may serve to collect good snippets here in lieu of a real central repository. To use, click "edit", and fetch the snippet's markdown source code.  Note: For these snippets to be easy to copy&paste, do not use the editor's linking method, but inline links, like so: [This is a link](http://www.this.is.the.url)    might help too:  See [so].


I remember changing some values to disable Deep sleep mode and hibernation a few months ago, and realised that my battery drains faster now. I just want to revert all settings to default. I changed some back such as hibernationmode 3, but not sure if I'm missing anything else.  Are these values normal for a 15" Retina Macbook Pro ?  (I'd appreciate if anyone can crosscheck with theirs if you didn't tamper with the settings in pmset -g )  On power :   Active Profiles: Battery Power       -1 AC Power        -1* Currently in use:  standbydelay         7200  standby              1  womp                 1  halfdim              1  hibernatefile        /var/vm/sleepimage  darkwakes            1  gpuswitch            2  networkoversleep     0  disksleep            0  sleep                0  autopoweroffdelay    14400  hibernatemode        3  autopoweroff         1  ttyskeepawake        1  displaysleep         60  acwake               0  lidwake              1   and on battery :  Battery Power       -1* AC Power        -1 Currently in use:  standbydelay         7200  standby              1  halfdim              1  hibernatefile        /var/vm/sleepimage  darkwakes            0  gpuswitch            2  disksleep            0  sleep                180  autopoweroffdelay    14400  hibernatemode        3  autopoweroff         1  ttyskeepawake        1  displaysleep         5  acwake               0  lidwake              1   Thanks


Is it possible to place random points within certain radius from a point?

Similar to how you can place random points within lines and within a polygon.


Comment upvotes aren't removed when the vote owner's account is deleted

I recently realized by accident that, when deleting your account, your comment upvotes are not removed, unlike up/down votes. Just as an example, I posted  comment on a site where I didn't previously have an account, and upvoted it 10 times by deleting and recreating my account (hopefully that's not considered abuse because I was testing a bug on a useless comment).  Supposedly, all votes are supposed to be removed when the owner's account is deleted (except in the case of high reputation users). Is it intentional that comment votes are kept? If so, why?


Hello everybody ~ I am fresh off the newbie tree and waving good bye to Windows through the rear view mirror.   I just started up an old machine that has a fresh install of 8.10 on it and has never been used since.    As far as I can tell there is no gui desktop on it.  I would like to update it to the latest, 14.x?   How do I update?  Do I just over write the 8.10 with the latest?  do I wipe the 8.10 first then install?  Can anyone please advise on this?  Many thanks.


How to change the perspective of an image in Photoshop?

I have a site screen shot(like this - ), and i want to rotate it to "perspective view" like the below image.     How i can do that? Google hinted nothing about this problem.


Connecting to a Synology Media Server database

Synology NAS's provide a multimedia server backed by a PostgreSQL database. You can connect to that database from an SSH session: sudo su - su - postgres psql mediaserver postgres  Now, I'd love to be able to connect to the database from any computer on my home network, e.g. using pgAdmin, rather than through an SSH terminal. My NAS is not exposed to the Internet and is behind my router's firewall, so I only need to open this to computers on my home network. Can anyone guide me on how to get there? I have no knowledge whatsoever on PostgreSQL, as I'm more experienced with MySQL.


Show suggestions when I type questions on mobile site

Recently, I have got lots of questions closed as duplicate because of that. I think, it's time this feature should be added to mobile site as smartphones can handle that today (my mid-range Android smartphone can handle that on desktop site).


$f$ is holomorphic then there exists $F$ such that $f=exp(F)$

Let $\Omega$ be a domain and $f$ is a holomorphic function with no zeros in $\Omega$. Suppose for infinitely many positive integer $k$, $f$ has a holomorphic $k$ th root. Prove that there exists a holomorphic function $F$ such that $ f=e^F$.  My try: I guess the argument principle might be useful here. But i don’t know how to prove it. When domain is simply connected, such result can be proved by letting $F(z)=F(z_0)+\int_{z_0}^z\frac{f’}{f}$.


Linear mixed model in R; modelling fixed effects with multiple levels and interactions. Help!

I am new to R and to mixed linear modelling. I have a dataset with variables from a cross-sectional study looking at fractional anisotrophy (a property of the brains white matter) in 6 different white matter fibre tracts in the brain. For each fibre tract there are 2 measures (one from each hemisphere). There are 66 participants divided into two groups. We want to control the group comparisons for differences in age, the average FA volume across the brain (wholebrain FA) and tract volume.  I assume that Group (Patients/Controls), Tract (CB/SLF1/SLF2/SLF3/UF/OFST) and Hemisphere (Left/Right) are fixed effects and that Subject (n=66) is a random effect. I also assume that Age, Wholebrain FA and Tract volume should be modelled as fixed effects. For Age and Wholebrain FA there is one value for each participant, but for Volume there is one value for each observation. The attached picture presents the table in the long format. For each subject there are 12 observations.    We hypothesized that there would be group difference in each of the six fibre tracts. We had no a priori assumptions about the hemispheres but would like to explore this post-hoc. We would also like to explore associations between Age and FA in different tracts.  My suggested model look like this  mixed.lmer <- lmer(FA ~ Age + Wholebrain_FA + Volume + GroupTractHemisphere + (1|Subjects), data = DTI)   Question 1: Given that Tract and Hemisphere are assumed to be fixed variables but also are within-subject variables, are they correctly modelled? I am having a hard time understanding how the model "understand" that these variables have multiple levels from the way it is written above.  Question 2: The Volume variable is a within-subject variable whereas Age is a between subject variable. Should they then not be modelled differently?  Question 3: Whether or not to include a three-way interaction is a major debate in my research group. Some saying that for practical purposes its impossible to really make sense of it. Other say it can guide the decision of whether or not to test differences between groups for each hemisphere in each tract. Including a three way interaction to the model is likely to change the results significantly so it seems pretty important to get it right the first time. Any thought on this? Is it being a criminal to include it?


"Sorry, we are no longer accepting questions from this account."-Rule too strong?

Maybe I was just a bit unlucky: I got some down votes, one questions has been moved to Ask Different and another question has been closed as exact duplicate (and it's even not a duplicate!) and now I'm banned to ask questions.  Since it's of course impossible for me to determine the number of cases which are similar to mine I can't say if it's true: but in my opinion the question ban rule is a bit too strong.


Taiwanese traveling to Europe via Istanbul, do I need a transit visa or e-visa?

I am a Taiwanese passport holder , will travel to Europe transit in Istanbul for 2 hours (inside airport only) , do I need to apply for a transit visa or an e-visa?


Black borders with external monitor on MBA 2013

I have a problem that I'm not able to fix. I'm getting black borders, some king of margin. The display doesn't use the full space in the monitor. I have a total of four monitors in my house and three TVs. I only get this problem with one monitor.  Note that I don't have this problem with my Mac Mini with the exact same monitor... only with my Macbook Air. I tried to plug the monitor with TB->DVI and with TB->HDMI. Same problem. I tried to switch cable. Same problem. I have a DIAMOND USB 2.0 DVI ADAPTER, and when I use it, I don't get any black border.  I have no "overscan" setting in the System Preferences.  My monitor is a I-INC iH282. There is no settings in the menu to adjust overscan or something like that.  Any idea why it does that? I spent my two last evening trying to find a solution on Google.  Thanks in advance!


Get value of select on change with class name

I am using jQuery to add select in each row of a table. The selects are assigned a class name.  Now, I need to get the value of the select on change using this dynamically assigned class name.  $select = $('<select class="medName"></select>');  for(var i = 0;i < tmp.length-1; i++){                 $option = $('<option>'+tmp[i]+'</option>');                 $select.append($option); }   Here tmp contains data fetched from backend.  Finally,       var $row = $('

');     var $data1 = $('	');     var $data2 = $('	');     var $data3 = $('	');     var $data4 = $('	');      //alert($select.html());      $data1.append($select);     $data2.append($type);     $data3.append($text);     $data4.append($label);      $row.append($data1);     $row.append($data2);     $row.append($data3);     $row.append($data4);      $row.insertAfter('#CashMemoBody');   This works perfectly fine.  Now when I do,   $('.medName').on('change', function (e) {         var val = $(this).find('option :selected').html();         alert(val); });   I do not even get an alert.  Inspect Element shows, that the classes are properly assigned.  Whats going wrong ?  Here the problem is NOT only dynamic binding, but also getting the value of the selected option. None of the provided solutions seem to work here. Hence the question.


How do I disable the "Show cursor when ctrl is pressed" option in 13.04?

I can't find it anywhere, and it's interfering with my work. I tried it just for fun, but now I can't figure out how I turned it on! Please help. Tweaks, code, or whatever. I need it disabled. Thanks!


How to route mail server from both internet and intranet?

We have a mail server configured in Ubuntu 12.04 with postfix, dovecot and roundcube. It has two interfaces, one with real IP and one with private LAN IP. Incase of intranet we have branches and head office, head office is connected directly through layer 3 switch and different VLAN and different IP block, branches are connected through core router.   The mail server is working fine with the internet domain and in case of intranet we can browse webmail by the local IP from our head office. But the problem is that the webmail is not accessible from the branches.   ICMP reply from branches to server and from server to branch is okay. Trace route from branches to server is okay but from server to branch it can't trace after 2 hop. The webmail page shows broken from branches. Already tested using a simple index html file, it also shows broken page from branch.   The default gateway is towards the real IP. We have some more servers with other applications in this IP block which are working fine from the branches. As per my troubleshooting it might be the routing issue as the default gateway of the server is towards Internet instead of intranet.   Please help me how to resolve the routing.


Call change event of an input programatically

I'm trying to programatically trigger the onchange event of an input that has the source below :  <input class="_2hvTZ pexuQ zyHYP" id="f1d5fcd30110a5c" aria-label="Phone number, username, or email" aria-required="true" autocapitalize="off" autocorrect="off" maxlength="75" name="username" type="text" value="">   I can see on devtools this input has a change listener attached, as you can see on the image at the end of the question. What i'm trying to do is call this event programatically, using the code below :  document.getElementById('f1d5fcd30110a5c').onchange();   But i get the error :  VM834:1 Uncaught TypeError: document.getElementById(...).onchange is not a function   How can i trig the attached event listener programatically using JS ?


Why is the Cartesian product of $A$ and $\varnothing$ empty?

Given two sets $A$ and $\varnothing$, where $\varnothing$ is the empty set. The Cartesian product is defined by  $$A \times \varnothing = \{ (x,y) \mid x \in A, y \in \varnothing \}$$  Why is $ A \times \varnothing = \varnothing$?


I just installed Ubuntu 13.10, but I can't locate my Dropbox icon, which used to reside next to the time, volume controls and such, in the upper right corner of my screen.  Dropbox icon is no longer shown, how can I turn it on?


In Inno Setup is it possible to add conditional statements to what in the [Run] section gets executed?

Alternatively is it possible to manually update the built in progress bar? Basically I have 2 MSIs included and using Inno Setup as a bootstrapper, and depending on user input one or both of the MSIs are to be installed.  I have something working using Exec statements in CurStepChanged but it doesn't update the progress bar as the files are extracted and it looks like the installer is stalled.  I guess the end result is I want some progress bar updates while the files are extracted to the temp folder.  The following is my current code:  procedure CurStepChanged(CurStep: TSetupStep); var     ResultCode: Integer; begin     if(CurStep = ssInstall) then begin         if(InstallServer) then begin             ExtractTemporaryFile('ServerSetup.msi');             Exec('msiexec',ExpandConstant('/i "{tmp}\ServerSetup.msi" /qb INSTALLDIR="{code:GetInstallPath}\Server\" ALLUSERS=2'),'', SW_SHOW, ewWaitUntilTerminated, ResultCode);         end;         if(InstallClient) then begin             ExtractTemporaryFile('ClientSetup.msi');             Exec('msiexec',ExpandConstant('/i "{tmp}\ClientSetup.msi" /qb INSTALLDIR="{code:GetInstallPath}\Client\" ALLUSERS=2'),'', SW_SHOW, ewWaitUntilTerminated, ResultCode);         end;     end; end;


Blender not starting on Windows Remote Desktop

I got a very tricky problem: Let's begin in the past. I got a Workstation. In the past it ran Blender 2.78b with a Nvidia Quadro FX1800 as Graphics Card. For Rendering, I used the CPU. I used another Computer to work on the Workstation via Windows 10 Remote Desktop Connection. The Host Computer (The Workstation) has Win 10 Pro, the Client Win 10 Home. I bought a new Graphics Card for rendering: ASUS ROG Strix GeForce® GTX 1080. I replaced the Quadro with it. I started the PC and Blender (still 2.78b) and rendered the Pavillon Demo Scene. Everything worked perfectly. But when I tried to start Blender via Remote Desktop and got this:    I also tried to use TeamViewer like they mentioned in , but got the same error. I also tried Blender 2.78c, but got also the error message.  Does someone know or experienced the same problem?


Zooming to specific polygon boundary Openlayers

I want to zoom to specific polygon boundary of some polygon layer. How can I do this.The map layer is WMS layer.


Stirling numbers of the second kind on Multiset

$S(n, k)$ count the number of ways to partition a set of $n$ elements into $k$ nonempty subsets. What if there were duplicate elements in the set? That is, the set is a ?


I have installed ubuntu 15.04 by erasing hard disk.During installation, I haven't done the partition.So, can anyone tell me how to do it now? i'm attaching screenshot of gparted


apex batch job schedule issue: "[REQUEST_RUNNING_TOO_LONG] Your request was running for too long, and has been stopped."

A followup to the issue I was having yesterday, so I've successfully created a schedule job to delete AS records every hour.  global class sharedeletebatch Implements Database.batchable<sobject> {       global final string query;      global sharedeletebatch(string q){            query=q;      }       global Database.QueryLocator start(Database.BatchableContext BC){        return Database.getQueryLocator(query);      }      global  void execute(Database.BatchableContext BC,List<SObject> scope){          delete scope;      }     global void finish(Database.BatchableContext BC){     }   }  global class deleteaccountsharebatch implements Schedulable {        global void execute(SchedulableContext SC)     {         string str='select id from AccountShare where lastmodifiedbyid =\'0050P000007Kfy2\' limit 5000';         sharedeletebatch bdt=new sharedeletebatch(str);         Database.executeBatch(bdt);         system.debug(bdt);           }    }   then I run this in anonymous window.    deleteaccountsharebatch m = new deleteaccountsharebatch(); String sch = '0 0 * * * ?'; String jobID = system.schedule('Hourly Job', sch, m);   The problem I'm having is that it keeps giving me "[REQUEST_RUNNING_TOO_LONG] Your request was running for too long, and has been stopped." error no matter how small I make the limit of the query.  So is that even the issue? Is there any other option or approach to mass delete a bunch of records on a schedule? I had no success with data loader either, similar 'been 10 min time out' error.


Does closing the lid put a MacBook Pro to sleep? Would it hurt the computer if I carry it around without shutting it down?

When I first got my MacBook Pro, it took less than 30 seconds to start up. Now, after several months, it takes about two minutes to startup and I can tell that it is not as responsive when using some applications (it was fast before).   I am wondering if it is because I'm not shutting it down that causes the lag during startup.


Standard nomenclature for component types

What prefixes should be used on reference designators for components of various types?  I think we can all agree that "R##" refers to a resistor, "C##" refers to a capacitor, and "L##" refers to an inductor.  Beyond that, it appears to be a mishmash of conventions.    I've seen both "IC" and "U" used for chips.   "Q", "T", and "M" have been used for transistors and MOSFETs.  Ordinarily, "D##" is used for diodes, but LEDs and Zeners get special treatment on some boards.    What standards are available for reference, and who endorses them?  JEDEC, ISO, IEEE, and other standardization bodies are welcome references (though I'd prefer an inexpensive standard), but I'm also curious to see what's used at various companies other than my own.    Edit:  What I'd really like to see is a list in an answer here which complies with the standard (even if it's just a quote).


Probability of collecting all prizes from cereal boxes

Each cereal box contains 1 of 5 uniformly distributed prizes.  If you open 10 randomly selected boxes, what is the probability that you will get all 5 prizes?  More generally, is there a formula you can use to solve this when the number of prizes is x and the number of boxes is y?


I discovered an interesting bug in the HNQ list just now.    The title of a Money SE question is .  It displays in the HNQ list incorrectly, however; notice how part of it is italicized, and the dollar signs are not displayed:


Let $H \subset G$ a subset non-empty of finite cardinality of a group   $(G,\circ)$ such that $h_1 \circ h_2 \in H$ for each $h_1,h_2 \in H$.   Then $(H,\circ)$ is a subgroup of $(G,\circ)$.   In order to show that it is a group, I already know that $h \circ 1_G = h$, for $h \in H$, but I am not able to bring the $1_G$ in our subset $H$.  I don't know how to use it that our subset cardinality is finite and non-empty. Does someone could help me on this?


I am making a diagram using Tikz in an attempt to match the one below.    So far I have this:    My problem is that the two paths from each 'trigger' node going into the 'susceptibility' node only converge on the western side of it. How do I get them to converge in the middle of the gap like in the first image? My code for the paths is as follows:  \path[draw]     (trigger1.east) -| (susceptibility.west); \path[draw]     (trigger2.east) -| (susceptibility.west);   I understand that I need to have a path shape more like -|- rather than -| to achieve what I need, but I get an error saying 'cannot parse this coordinate' when using -|- . Is there any way to get a path with the -|- shape?  For context, I am using Overleaf.  This is my first time submitting a question here so please let me know if more info is needed or the images are broken.


I'm new to Ubuntu. Whenever I try to install anything using sudo on my PC, it shows:  The following packages have unmet dependencies:     google-chrome-stable : Depends: libappindicator1 but it is not going to be installed   I tried the following commands:  sudo apt-get clean sudo apt-get autoclean   but none of them worked. Please tell me how can I fix this error.  P.S.: I'm using Ubuntu 16.04 LTS (Xerial Xenus).  Such as when I try to install VirtualBox:  user@User:~/Desktop$ sudo apt-get install virtualbox Reading package lists... Done Building dependency tree        Reading state information... Done You might want to run 'apt-get -f install' to correct these: The following packages have unmet dependencies:  google-chrome-stable : Depends: libappindicator1 but it is not going to be installed  virtualbox : Depends: virtualbox-dkms (>= 5.0.40-dfsg-0ubuntu1.16.04.1) but it is not going to be installed or                        virtualbox-source (>= 5.0.40-dfsg-0ubuntu1.16.04.1) but it is not going to be installed or                        virtualbox-modules               Depends: libgsoap8 but it is not going to be installed               Depends: libvncserver1 (>= 0.9.10) but it is not going to be installed               Recommends: virtualbox-qt (= 5.0.40-dfsg-0ubuntu1.16.04.1) but it is not going to be installed               Recommends: libqt4-opengl (>= 4:4.5.3) but it is not going to be installed E: Unmet dependencies. Try 'apt-get -f install' with no packages (or specify a solution).   I am not able to install anything. Plus, my Chrome is installed and working. However, when I try to install it with sudo, this error occurs:  ~/Desktop$ sudo apt-get install google-chrome-stable_current_amd64.deb Reading package lists... Done Building dependency tree        Reading state information... Done E: Unable to locate package google-chrome-stable_current_amd64.deb E: Couldn't find any package by glob 'google-chrome-stable_current_amd64.deb' E: Couldn't find any package by regex 'google-chrome-stable_current_amd64.deb'


re python - Extract two different parts of a string

I'm trying to remove a certain part of a string but currently not getting the correct answer. The string is:  new_text = "'Bob' is currently 'Absent'. Hi, my name is Matt. 'Bob' is currently 'Active'. Bob: Hey Matt"   I want the two substrings: 'Bob' is currently 'Absent'. and 'Bob' is currently 'Active'. to disappear. The name "Bob" may toggle between names with alphabetical and non-alphabetical characters. "Absent" and "Active" are two of the more common statuses displayed, however, I'd like to keep track of any string inside the single quotes.  This is the final sentence I want to return: Hi, my name is Matt. Bob: Hey Matt.  Currently my code is:  re.sub(r"\'([\w\W\d]+)\' is currently \'[\w\W\d]+\'.\s", '', new_text)   And it's returning: Bob: Hey Matt  Can anyone help with this?


Can the suffix -wise be considered too inadequate/colloquial for a personal statement?

I am writing a personal statement for the very first time and I'm worried that the suffix -wise may sound too laid-back for a text of such genre. The sentence I want to write is similar to this:  Teaching-wise, being bicultural can be an advantage in that it...  I appreciate your help!


I want to find the derivative of a function $f$. If I manage to find a function $g$, whose derivative I know for all $n$ such that $$f(x)=\lim_{n\rightarrow \infty} g(x,n),$$ is it true that $$\frac{\partial f}{\partial x}(x)=\lim_{n\rightarrow \infty}\left( \frac{\partial g}{\partial x}g(x,n)\right)?$$  I'm asking this because I want to know $$\frac{\partial \theta}{\partial x_i}(||\vec{x}||),$$ where $\theta$ is the Heaviside step function.


prove that f is constant if $f(2^x)=f(3^x)$

I am trying to prove that when $f$ is continuous for all non-negative real number and $$f(2^x)=f(3^x),$$ then $f$ is constant. If $f(2^x)=f(3^x)$ then from here I can say that $f(2^x/2^n)=f(3^x/3^n)$ and then I can use limit when $n\to\infty$, but I am not sure how to make connection with $f(x)$ function itself to prove. Could you give me any hints? Thanks in advance.


Prove a differentiable function between banach spaces is continuous

I really don't know where to start with this problem. It intuitively makes sense from basic calculus knowledge but I have absolutely no clue how to show it. ,


Why am I prompted for the bitlocker recovery key upon startup?

I recently installed the Windows 10 Fall Creators Update. Now, each time I start my computer,  I'm prompted for the bitlocker recovery key. In response to each prompt,  I  enter the key hoping this will be the last time. But it isn't.  I've not noticed any other problems.  Once I'm logged in everything seems to run fine.  I have easy access to the key but it's a hassle to enter it every single time. I'm also not ready to rollback the update either... close but not there yet.  The computer is a two year-old Dell XPS 9550 with a single 500gb SSD running Windows 10 installed at the factory. It is regularly updated with  Windows patches and less frequently applied hardware patches.  Any ideas?


I read this link  But this answer doesn't look enough to me.  Can I have more explanations about uses of unions. I don't want any memory related examples like, this will take max 4 bytes (float occupy 4 bytes ).  union un{     char ch;     int iNum;     float fNum; };   So my question is,  what exactly the use of union?   why we need this?  Please help me, its confusing me. Thanks.


How to do a classification with only one variable?

I would like to classify individuals of a database by a single quantitative variable. Is hierachical clustering suitable to do this? If it is possible, how the algorithm work? If use hierachical clustering is not right, which other procedures or techniques could I use? My purpose is not classify the variable, but individuals. So decision trees are not suitable.


Here is the problem I was given: Write a program that takes website names as keyboard input until the user types the word 'stop'. This program must also count how many of the website names are commercial website names (end with .com) and output that count.   Here is the problem I keep running into: for example, if I input 'facebook.com', 'google.com', and 'pintrest' the output will say I entered three commercial sites, even though only two of my inputed sites end with com. Can someone explain where I went wrong and how is the best way to fix it? Here is my code.  import java.util.Scanner;   public class NewClass  { public static void main( String [] args)  {      int count = 0;     String commercialNames = "com";     final String SENTINEL = "stop";     String website;      Scanner scan = new Scanner(System.in);     System.out.print("Enter a website, or 'stop' to stop > ");     website = scan.next();      String substring = website.substring(website.length()-3);      while (!SENTINEL.equals(website))      {         if(substring.equals(commercialNames))         {              count++;         }         System.out.print( "Enter the next site > ");         website = scan.next();     }           System.out.println( "You entered " + count + " commercial websites.");         }     }   Thanks!


Do epimorphisms map identity to identity?

Suppose $f:R\rightarrow R'$ is an epimorphism of rings with identity, can we have   $f(1_R)=1_{R'}$ ?   I think I should assume that $f(a)=1_{R'}$, but I don't know how to continue. Thanks for any help in advance.


Problem with proof of almost sure divergence

Let's define $$P(X_n=1)=\frac1n,\;P(X_n=0)=1-\frac1n$$ $(X_n)$ are independent. I want to show that does not exist X such that :  ${\displaystyle {\overset {}{X_{n}\,{\xrightarrow {\mathrm {a.s.} }}\,X.}}}$  We know that  $$ X_{n} \xrightarrow{\mathrm{a.s.}} X \iff \mathbb{P}\left(\omega:\lim_{n\to \infty}X_n(\omega)=X(\omega)\right)=1.  $$ $(X_n)$ is constant sequence so the limit of $(X_n)$ is $0$ or $1$. Let's consider $\sum_{n=1}^{\infty}P(\omega:X_n(\omega)=1)=\sum_{n=1}^{\infty}\frac1n=\infty.$  $\sum_{n=1}^{\infty}P(\omega:X_n(\omega)=0)=\sum_{n=1}^{\infty}1-\frac1n=\infty.$  So by the second Borell-Cantelli lemma i get :   ${\displaystyle P\left(\bigcap _{n=1}^{\infty }\bigcup _{k=n}^{\infty }(\omega:X_n(\omega)=0)\right)=1.}$  ${\displaystyle P\left(\bigcap _{n=1}^{\infty }\bigcup _{k=n}^{\infty }(\omega:X_n(\omega)=1)\right)=1.}$.  And now i want to tell that $(X_n)$ cannot has limit because he oscillates between $0$ and $1$. Am i thinking correctly ?


Prove this statement (inequality): $|x-y| \leq|x-z|+|y-z|$

$x,y,z$ $\in\mathbb  R$ then $|x-y| \leq|x-z|+|y-z|$  Prove this statement.  I thought it was the triangle inequality, but I can't seem to end up with the correct order.


How to show 'similar' commands when you forget the exact command

If I get this:  No command 'pdf' found, but there are 16 similar ones pdf: command not found   How do I see the 16 similar commands?


How to send user password during registration?

How to send user password during registration. I have to send html email when user register in the site using rules module in drupal 7 and i have to send the username and user password in that mail. i used [account:name] and [account:password] or [user:password] but i did not get the user password on my mail.


How to relate a Case with a Contract using Apex?

Use case : Once contract is inserted with :  record type = B2C AccountId = Case.AccountId ContactId = Case.ContactId GEG_Correspondance_Offre_Produit__r.Type_Energie__c = Case.GEG_Correspondance_Offre_Produit__r.Type_Energie__c  Then relate all cases respecting these criteria ** Here's my Trigger** trigger Contrat_Trigger on Contract (after insert) {   List<Case> cases = [Select id , GEG_Contract_Requete__c , ContactId, AccountId from case where Status ='Clôturée' and RecordType.Name  = 'Demande de Souscription' and GEG_Correspondance_Offre_Produit__r.Type_Energie__c = '0'];  List<Id> ids =  new List<Id>(); for (Contract con : Trigger.new){     ids.add(con.Id);      }  for (Contract con : [select Id , RecordType.Name from contract where Id in : ids]){          for(Case c : cases){                      if(con.AccountId == c.AccountId && con.GEG_Contact_Titulaire__c == c.ContactId && con.GEG_Correspondance_Offre_Produit__r.Type_Energie__c == c.GEG_Correspondance_Offre_Produit__r.Type_Energie__c){                 c.GEG_Contract_Requete__c = con.Id;             }            cases.add(c);          }                       }     update cases; }  My trigger doesn't work as expected , does anyone have an idea ?


How to access a clicked URL in a URL handler application created in Automator

I'm currently trying to modify the default URL handling behavior in OS X. I would like, when clicking on any link outside of a web browser, to copy this URL to the pasteboard instead of opening it in the default web browser – for instance, clicking a link in a Skype conversation should copy this URL to the OS X pasteboard instead of opening it in Firefox (which is currently my default web browser).  I have thought about solutions, but I’m currently unable to implement one. If I can create an application that puts URLs into the pasteboard that are sent to it, and can set this application as the default web browser, I would be able to achieve my goal.  I created an application with Automator that executes the shell command pbcopy and have set this application as my default web browser, but I didn’t get the expected result. I did some testing and I can confirm that the application runs on clicking on a link, however, I cannot get the URL passed to the application / shell script. I tried both stdin or a passed argument, but without success.  Is there a way for an application created with Automator to retrieve a clicked URL and send it to pbcopy, when that application is set as a (default) handler for URLs?  Alternatively, is there a better way to create a fake web browser that takes the input and puts it in the pasteboard than Automator? Or is there any other way that I can achieve my goal without a custom application / script?


How to draw uml diagram as figure in LaTeX document?

I have some code for uml diagram that produces UML diagram as pdf. I want to include these UML diagram in my lab report where these uml diagram are shown as figure. There is a solution that making the screen shot of those UML and then add these in document. But, I want to add those as raw latex code.  For example:  \documentclass{article} \usepackage{pgf-umlcd} \begin{document} Some text. \begin{figure} \begin{tikzpicture}   \begin{class}[text width = 8cm]{LaTexLanguageBehavior}{0,0}     \attribute{$\sim$ com.alhelal.textpad}     \attribute{$-$ uniqueInstance : LaTexLanguageBehavior}     \operation{+ getUniqueInstance : LaTexLanguageBehavior}     \operation{+ runCode(file : File) : BufferedReader}     \operation{+ buildCode(file : File) : BufferedReader}     \operation{+ setHighlightableText()}     \operation{+ setAutoCompletableText()}   \end{class}   \node [above=3mm] at (current bounding box.north) {Singleton Pattern}; \end{tikzpicture} \end{figure} Some text. \end{document}


I've been searching and came across to a lot of very useful information already on the VWP and implications on staying longer than 90days under the VWP. I'm fully aware of the fact that you can stay for a maximum of 90days under the VWP, and I have read a lot about other experiences but I didn't came read any topics about my scenario which is as follows.  I'm currently staying under the VWP in the US and my return flight back home is scheduled on April 5th. As I am planning to stay another 3 months in the US I considered the following solution to stay for another while.  Potential scenario  If I would fly to Colombia by the end of March and come back to the US, lets say on April 2nd, before my scheduled home flight. My understanding is that in general, leaving the country to Colombia and coming back would count as a reentry, and if I get admitted in to the country under the VWP I would get another 90days. After the admission I will cancel or reschedule my flight home to a later date (within the new 90 days).  However, what I couldn't find is: - Do I get a new reentry, even though I reenter before my initial scheduled home flight? I would assume that my trip to Colombia counts as "leaving the country" for my first admission to the US? - If yes, can I change my initial flight afterwards without having any troubles?  - Does anyone has any experiences with this and would you recommend to change my home bound flight before or after the reentry?  Hoping to hear some experiences from people who did this before. As mentioned, I did read a lot about this and I am aware of the risks, but I'm rather hoping to hear some experiences, especially suggestions about if and when to change my home bound flight would be very helpful.  Thx all!