A graph $G$ is bipartite if and only if $G$ can be coloured with 2 colours

I've been stuck on this question for some time, can anyone please help me out with it...  Definition: A graph $G = (V, E)$ can be coloured with $k$ colours if $\forall v \in V$, $v$ is assigned exactly one of $k$ colours and $\forall e = (u, v) \in E$, $u$ and $v$ are coloured with different colours. Prove that a graph $G = (V, E)$ is bipartite if and only if $G$ can be coloured with 2 colours.


How to set up multitenant Route53 subdomains with parent domain not on Route53?

My goal is to be able to add/drop subdomains for a multi-tenant app via Route53: tenant.example.com. Account provisioning should place the new tenant on a hosting node and then add the newly onboarded tenant subdomain to Route53. The parent DNS is currently handled by a 3rd party (dnsmadeeasy). Currently DNS provider has something like this:  example.com -> A -> <someIP> example.com -> MX -> <mailhost> mail.example.com -> CNAME ->  <mailhost> www.example.com -> CNAME -> example.com example.com -> NS -> <several provider name servers>   I'm also pretty sure the DNS parent provider (dnsmadeeasy) has a SOA record too which is implicit (not shown in management UI). So I did the following:   I added a wildcard hosted zone in Route53: *.example.com. This has 5 records right now, 4 NS records with various name servers and a SOA record I added the Route53 NS records to the parent DNS provider (dnsmadeeasy)  *.example.com -> NS -> <Route53 name server for hostzone above>   My thinking was that now I can start adding A records in the Route53 zone for each tenant:  tenant1.example.com -> A -> <tenant1 hosting IP> tenant2.example.com -> A -> <tenant1 hosting IP> ...   But trying to add A records in Route53 results in tenant1.\052.example.com which is not what I want. And I'm not even sure it will work.  My question is whether this is a correct way to go ahead or I'm of the wrong path.


Sum of an infinitive series, with variable being a natural number

I have the following problem  Let $n$ be a natural number. What is the sum of $1+2+3+...+(n-1)+n$  I'm not 100% certain what would be a correct way of calculating it. What I've done so far is look at the first and second first and last term. $1+n$ and $2+(n-1)$.  So I have $2n-1+2+3+...$. So that means the sum is $∞$


I'm using Bash in Ubuntu 20.04. I have file: Hello hi 123 if a equals b you one abc two three four dany uri four 123  I need to found with sed only- the lines with only 4 words . This is the code I wrote and it does not work, it prints exactly the file. sed "/[a-Z0-9+]{4}/g" F1


Show that $\|A\|_\infty \leq \sqrt{n}\|A\|_2$.

Show that $\|A\|_\infty \leq \sqrt{n}\|A\|_2$ for any $m \times n$ matrices.  I know $\|A\|_\infty$ is the largest row sum of the matrix, but I'm not sure how to compare with $\|A\|_2$ especially since matrix 2-norm is induced by some other vector. All hints will be appreciated!


does 14.04 support all the softwares which work in window 8.1 like photoshop , corel draw, and all games like nfs, xmen, pes ? I don't need any antivirus for this 0S , right ?  Pls reply


What is meant by Input clamp current/Output Clamp current in micro controller datasheet?

While reading a , I found the parameters Input clamp current / Output Clamp current. Where do I consider these specifications?


I can login as any user, but not as a root user in  centos 7. When I type the command su and enter password ,it gives me login incorrect message. What could be the issue?


I managed to somehow completely delete the Smooth brush in Blender. I've tried closing and opening the project, uninstalling and re-installing the app...nothing! Thanks in advance :) PS: if you know how to delete that repeated brush, that would be awesome as well!


How to remove points which are too close to each other?

I have a bunch of data points, however I think that some might be too close to each other due to sampling error and could therefore have an impact on my subsequent analyses.  How can I remove data points which are less than 200 meters from each other?  I'm using ArcGIS 10.2


How to set up a host to IP mapping on unrooted Android?

I've a website running on my computer, and I want to test it from my Nexus 7 tablet. I.e. over the local WiFi LAN. If I type in the IP address it connects, but shows the wrong web site, because I'm using named virtual hosting.  So, what I want to do is be able to type mysite.local in to Chrome/Firefox on the Nexus, have them convert that to 10.1.2.3 (or whatever the local IP address is), then call the 10.1.2.3 server giving mysite.local as the Host to request.  My Question: Does an Android 4.x tablet have an /etc/hosts files, or equivalent, that I can edit? (Without having to root the tablet, or anything like that.)  On my Linux computers I do this by adding an entry in /etc/hosts:  10.1.2.3  mysite.local   (Or Windows\System32\drivers\etc\hosts on a Windows machine does the same.)  BTW, this is a semi-duplicate of , but that question was for Android 2.2, where apparently it was not possible. (One of the alternative ideas suggested there was configure DNS at the local router, but as far as I can tell my router does not do DNS locally so does not have that option. I could set up my own DNS server to do this, but that feels like a Big Job Solution.)


Express a set of number with binomial coefficients in terms of $n$

Hi I'm working on my scholarship exam practice but I got stuck at my last question, could you please have a look? I'll write every part of question so you know the big picture. I have marked the problematic question in bold below. This question only assumes knowledge in high school or pre-university level.  Draw a circle $C$ on a plane. Put $n$ distinct points on the circumference of $C$. Join any two of the $n$ points with a chord. Suppose that no three chords intersect at any one point inside $C$. Let $c_n$ be the number of such chords, $i_n$ that of intersections of the chords inside $C$, and $r_n$ that of regions in $C$ bounded by an arc and/or some chords. Fill in the blanks with the answers to the following questions. (1) Find $c_1, c_2, c_3, c_4, c_5, c_6$ and write their values in this order.  The answer of this part checked with answer key is $0, 1, 3, 6, 10,$ and $15$ by drawing 6 different circles with n dots from 1 to 6 each circle, connecting each dot and counting number of chords.  (2) Find $i_1, i_2, i_3, i_4, i_5, i_6$ and write their values in this order.  The answer of this part checked with answer key is $0, 0, 0, 1, 5,$ and $15$ by counting intersections of chords.  (3) Find $r_1, r_2, r_3, r_4, r_5, r_6$ and write their values in this order.  The answer of this part checked with answer key is $1, 2, 4, 8, 16,$ and $31$ by counting the regions.  (4) Express $r_n$ with binomial coefficients in terms of $n$. (For binomial coefficients ${m}\choose{k}$, note that ${m}\choose{k}$$= 0$ if $m<k$.)  I got stuck at this question since I got nowhere near the answer key. My approach is below: ${n}\choose{k}$$=\frac{n!}{(n-k)!\cdot k!}$ Pick $n=2$ and $n=3$ and substitute the values from (3) into the equation, ${2}\choose{k}$$=\frac{2!}{(2-k)!\cdot k!}=2$ ${3}\choose{k}$$=\frac{3!}{(3-k)!\cdot k!}=4$ $\frac{2!}{(2-k)!\cdot k!\cdot2}=\frac{3!}{(3-k)!\cdot k!\cdot4}$ And $k$ will be weirdly equal to $\frac{3}{2}$ leading to binomial coefficient ${n}\choose{3/2}$, which is incorrect. The answer key provided is $1 +$${n}\choose{2}$$+$${n}\choose{4}$. How can we get to this answer? And, how is my method faulty?


If I create an application on my Mac, is there any way I can get it to run on an iPhone without going through the app store?  It doesn't matter if the iPhone has to be jailbroken, as long as I can still run an application created using the official SDK. For reasons I won't get into, I can't have this program going through the app store.


Example of element of double dual that is not an evaluation map

It's well known that if $V$ is a vector space over a field $F$, then there is a natural injection from $V$ to the double dual $V^{**}$, which associates to every $v \in V$ the evaluation map $\phi \mapsto \phi(v)$, where $\phi: V \to F$ is an arbitrary functional in $V^*$. It's also well known that this injection is an isomorphism if $V$ is finite-dimensional, as any finite-dimensional vector space has the same dimension as its dual.  My question is this: are there any nice, readily understood examples of infinite-dimensional vector spaces $V$ for which an element of $V^{**}$ that is not an evaluation map can be explicitly constructed (at least with the axiom of choice)? I find infinite-dimensional double dual spaces hard even to think about.


Change the word "Appendices" in TOC to "Bijlagen"

I am trying to change the name of the "Appendices" part in my Table of contents to the dutch word "Bijlagen".  So far I have this, but the word "Appendices" still appears in my table of contents:      \documentclass[11pt]{report} \usepackage[toc,page]{appendix} \renewcommand\appendixname{Bijlage} \renewcommand\appendixpagename{Bijlagen} \renewcommand\contentsname{Inhoudsopgave}  \begin{document} \tableofcontents  \chapter{Eerste hoofdstuk} \chapter{Tweede hoofdstuk}  \begin{appendices} \renewcommand{\thechapter}{\arabic{chapter}} \chapter{Eerste bijlage} Text eerste bijlage. \chapter{Tweede bijlage} Text van tweede bijlage. \end{appendices}  \end{document}


Are there any news about the release date of QGIS3

Since I will make a workshop on the new features of qgis 3, the members will ask the release date of QGIS3.  Having a look to   only shows 2.18 until the next year, QGIS 3 has completly disapeard from the road map until 2019...?


I am planning to have my own website and would like to ask some questions regarding about the organization (I don't know if this is the right term for it) of domain names.  Let me give an example:  If I have a domain named “www.joe.com” but is planning to have different websites or categories for my varied interests but would still retain the  “joe” name on my domain, would it be better to have a sub-domain instead?  Is that it?  Is this what would turn out:  www.joe.com             = my main site bookworm.joe.com        = a blog for my love of books travel.joe.com          = a blog for my travel experience food.joe.com            = a blog for my love of food and cuisine  I also notice that there are other websites that are like this: (this is just an example, but you get the idea)  www.personname.com          = main site www.personname.com/blog     = a blog for his site ( is this a subdomain now)  Everytime you go to the www.personname.com, you are then redirected to the www.personname.com/blog address.  Is it safe to say that the blog address is a sub-domain and for blogging only and then the www.personname.com is the main site?  What is the difference of this approach compared to the first example I've given above?  Cheers!


I just updated the Pokemon go app and it asked me to log in again and I'm back at the very start, please help!


I have a  that refuses to autofocus. When I mount the lens, turn on the camera, and press the buttons to begin autofocusing, nothing happens. I don't even hear the AF motor trying to do anything. I  related to focusing problems, but my serial number starts with 18..., putting it well outside the range of numbers covered by the notice.  I can focus the lens manually. The lens in question fails to focus on either of two bodies, and all my other lenses continue to autofocus on either body without any problem. The batteries in the bodies are fully charged. The contacts on both the camera bodies and the lens look clean, shiny, and undamaged.  Short of sending it in for repair, is there anything I can do to get the lens working again?


I created in emacs a bunch of (Chinese) flashcards with file extension .fls and they all had a file type "plain text document" and they all opened with emacs. I happened to open one of these files with Text Editor and this caused all of my new (or edited) files with *.fls file to be assigned file type "C source code" (and BYW without permission from me to do so.) In viewing the file properties window the "file type" is not changeable from any of the tabs. I can set these *.fls to open with emacs so the only problem is the file icon has a big blue C in the middle so the problem is mostly cosmetic. Nevertheless, I would like to fix this. The "answers" I have found so far seem only explain how to associate the the file type with an application to open it and not how to actually change the file type. So, how can I change the file type in Ubuntu 18.04?


How to fully uninstall python and reinstall it in Ubuntu 18.04

Python is not configured or broken in my system Ubuntu 18.04. Can anyone suggest command to uninstall python and reinstall only python3.6  I ran below command : sudo apt auto remove  Andd when I try to run "apt update" or "apt upgrade" getting below error Errors were encountered while processing:  apport E: Sub-process /usr/bin/dpkg returned an error code (1)


How to get accurate power of number after extraction of a root

I am trying to remake  but only with square and power of two, you can type a number and just click to get square root of two from the number, you can also click to make number squared. Everything works fine but after you click root and then power you get slightly different value. I tried a few javascript methods like toFixed() but for different values you have to sometimes round it and sometimes floor it for example after getting the root and exponentiating from:  2 it's 2.0000000000000004 so the result would have to be smaller 3 it's 2.9999999999999996 so the result would have to be bigger


Define bijection $Z^X \times Z^Y$ and $Z^{X \cup Y}$

I was given the following task  Define bijection between $Z^{X \cup Y}$ and $Z^X \times Z^Y$, $X\cap Y = \emptyset$  I have the following proof  We need to build a map $h$. Let's define it. $h(f)(a) = \begin{cases} z & a \in X \\ g & a \in Y \end{cases}$ Now we have to proof injectivity and surjectivity. Let's begin with injectivity. Assume that $f \neq f'$. Then $\exists a$ such that $f(a) \neq f'(a)$. Therefore $h(f)(a) \neq h(f')(a)$. Now surjectivity. $\left.f\right\rvert_X = g$ and $\left.f\right\rvert_Y = z$  Could you please validate my proof ?


BSDF the meaning of the colors of the dots

I would like to understand, in the Principled BSDF the meaning of colors (yellow, blue and grey) of the dots in the left hand side and the reason, why these dots cannot be connected as inputs to other node.


What values of alpha guarantee the convergence of $\sum _{n=0}^{\infty }\left( \frac {\alpha n} {n+1}\right) ^{n}$?

I have managed to use the root test and get as far as getting the limit to equal to $1$. But, I still need clarification on why the answer for the limit to this questions is $\alpha < 1$. \begin{align} \sum _{n=0}^{\infty }\left( \frac {\alpha n} {n+1}\right) ^{n}\end{align} \begin{align} \lim _{n\rightarrow \infty }\left( \left( \frac {\alpha n} {n+1}\right) ^{n}\right) ^{1/n} =\left| \frac {\alpha n} {n+1}\right| =\alpha \lim _{n\rightarrow \infty }\left| \frac {n} {n+1}\right|=1.\end{align}


I have read somewhere sometime ago (very specific, I know...), that it would not be correct to treat rate of change, i.e. any arbitrary $\frac{dy}{dx} \ $ as a fraction, and thus it is not possible to perform any algebraic manipulation with it. I should have questioned that when I have read it in the first place, I would not have been asking this question now then.  Anyway.. I have seen this "rule" being ignored many many times, e.g. $\displaystyle{\frac{dy}{dx} \equiv \frac{1}{\frac{dx}{dy}}} \ $ or $ \int a(y) \frac{dy}{dx} dx \equiv \int a(y) dy$. I don't understand how you can cancel $dx$ in the integral either, isn't it just a notation to say what to integrate with respect to?   I want to understand how is this possible. Thank you!


A man is sitting on a boat which is floating in a pond. If the man drinks some water from the pond, What happens to the level of water?   According to me, the level of the water in the pond should decrease. However, when I tried to perform it on a mini scale (I really did not have any means to get the correct answer) by putting a spoonful of water in the toy boat instead of a man drinking water (well, I hope both the actions are equivalent), I found that the level of water remains same. How?  Related: but doesn't answer my question .


Product selection or products selection?

I need to refer to a selection that contains zero or more products. This will be used in a marketing email that displays some products for sale. I consider the "selection" to be some kind of box in which I can put some products (no matter how many). To me, it's a "products selection", since the plural applies to the content of the selection. However, I have found  of "product selection" on the Internet. These did not seem to refer to "the selection of one product", but to the same as in my case. So what should I use: "product selection" or "products selection", and why?


is upgrade ubunto 19.10 to 20.04 now not available on ubuntu 19.10? I'm keep getting error when I'm doing sudo apt-get update -y   404  Not Found [IP: 91.189.95.83 80] Reading package lists... Done  is it cause ubuntu 19.10 does not supported no more? How should I upgrade 19.10 to 20.04


Is there any way to put my whole Recycle Bin on one hard drive?

Using Windows 10, I notice that each drive on my system has its own recycle bin. Is there any way to override this behavior and put the entire recycle bin on one drive, e.g. a hard drive, so as to avoid taking up valuable space on other drives, e.g. a SSD?


How to correctly write this norm symbol?

I would like to write a norm symbol of not two double vertical lines but rather two triple vertical lines. Currently I am doing it as \|| \cdot \|| instead of \| \cdot \|, but I have two issues with this typing: (1) it does not adjust the size of the vertical lines if, for some reason, the object replacing \cdot is too big, and (2) it does not look good; the space between each line is different.  How can I solve this?     Excuse me, but I didn't know how to correcctly tag this question.


Does $\sum\limits_{k=1}^n 1 / k ^ 2$ converge when $n\rightarrow\infty$?

I can prove this sum has a constant upper bound like this: $$\sum_{k=1}^n \frac1{k ^ 2} \lt 1 + \sum_{k=2}^n \frac 1  {k (k - 1)} = 2 - \frac 1 n \lt 2$$ And computer calculation shows that sum seems to converge to 1.6449.  But I still want to know:  Does this sum converge? Is there a name of this sum (or the series $\frac{1}{k^2} $)?


Solving the functional equation $f(x^2+f(y))=(f(x))^2+y$

Find all $ f : R\rightarrow R $ such that $f(x^2+f(y))=(f(x))^2+y, \forall\text{ x,y}\in R$  Thanks in advance!


Kernel driver not installed (rc=-1908) error in VirtualBox

Every time I try to run something in VirtualBox it keeps giving me an error, and I can't figure out how to fix it. I don't know how to fix it, and please be as detailed and easy to understand as possible, so I on't get confused. This is the error.   Kernel driver not installed (rc=-1908)  The VirtualBox Linux kernel driver (vboxdrv) is either not    loaded or there is a permission problem with /dev/vboxdrv    Please reinstall the kernel module by executing '/sbin/vboxconfig' as root.   where: suplibOsInit what: 3 VERR_VM_DRIVER_NOT_INSTALLED (-1908) - The support driver is not installed. On linux, open returned ENOENT.


For all $(x,y)\in\mathbb{R}^2$ a function $f$ satisfies $f (x+y)=f (x)\cdot f (y)$. If $f$ is continuous  at a point $a$, then show that  $f$ is  continuous  on $\mathbb R$ and  $f (x)= b^x$ for some constant  $b$.  My approach $$f (1)=f (1+0)=f (1)\cdot f (0)$$ Thus $f(0)=1$ and $$f(x+h)-f (x)= f(x)\,(f (h)-1)$$ I can prove the continuity  of the function. How can I prove that $f (x)=b^x$ for any $x\in\Bbb R$?


Syntax highlighting thinks entire code block is string

In 's second code block, there is a string assigned like this:  string xmlpath = @"C:\Users\Rick\Documents\Visual Studio 2010\Projects\Server\server.config\DC_Finalized\" + cboNetGuid.SelectedItem.ToString() + ".xml";   The rest of the code block after this is highlighted as though it is one long string (it treats any text that actually is a string as non-string plaintext).  It looks like the @ makes the highlighter treat it as a multi-line literal, and the string ending with a \ escapes the closing quote, causing the highlighter to treat the entire thing as a string.


I was in a clan and someone kicked me from it.   I think I'm stronger than him. Is there any way I can attack him? The only method I see to attack is random players. Can I attack a specific player?


I'm trying to search online for the string toUri().  Valid result will be Java's   But when I search google it return mostly toURI results.  When I search I discover that .  How can I still ignore results of toURI? Searching "toUri()" - "toURI()" didn't help.


Is it true that $\omega=\{0,1,2,3,\ldots\}$ in ZFC?

This is a bit of a philosophical question. According to "Set Theory" by Jech, the set $\omega$ of natural numbers is defined as the least nonzero limit ordinal. After thinking about this definition recently I found no reason why this set should neccessarily be restricted to contain only the numbers obtained by applying the successor operation to zero, what is the intuitive notion of natural number.   I did not even find a way to formulate the statement that all elements of $\omega$ are of this form.   To be more technical, is it in fact possible to consistently add an element $x$ to the theory together with axioms that assert $x\neq0,x\neq 1,\ldots$ ?


Is it possible to gain point survival estimates from a coxme object?

I have a coxme object: (Age, status) ~ F + X1 + X2 + (1|R1) + (1|R2) + (1|R3) Where F is an individual's level of inbreeding, X1 & X2 are covariate factors, and R1, R2 & R3 are random factors denoting non-independence between individuals, and breeding facility.   I understand that the coxme output gives me the % change in the rate of the event occurring due to inbreeding increase, but I'd like to get point estimates of survival to the 5th year of age for each inbreeding level from this model. With this, I'd like to calculate the effect of increasing inbreeding on survival to a specific point in time (giving us a rate which can be fed into population models for this species).   Seeing as there is no simple method to extract this data from acoxme object (e.g., survfit), is there a process by which I can extract it manually for specific points in time from my coxme fit?   Alternatively, would it be more appropriate to extract this data from Kaplan Meier curves for each inbreeding strata of the model without the random factors (I don't feel like it would be accurate, but I'm not 100% sure)?   My cox models may not be appropriate to use in determining this rate, but it's something that I've worked with a lot so far and I'd like to know if it is at all possible.   Any discussion, comments, advice would be greatly appreciated, Thanks.


Why does current remain constant in a series circuit although the rate at which they flow deceases due to the collisions they go through?

I am really confused and frustrated as I can't figure this out. If someone could clear my doubt, I'd be really thankful.   According to my textbook current is the rate of flow of charge, it is directly proportional to voltage provided the resistance remains constant. So, when current which is basically electrons carrying electrical energy, when they pass through a resistor or lamp or any other electrical component, some electrical energy gets converted into thermal energy, so the electrical energy they carry is reduced, right? And as they pass through a component they undergo collisions with the atoms which causes their speed to reduce, they will travel slower and therefore pass through the resistor much slowly, so as its speed reduces the current should reduce?   As current is the rate of charge, it's rate will definitely reduce due to the collisions it will go through, right? I understand that the “amount” of electrons will remain same as everyone says, but current just isn't “flowing electrons” it's the rate at which they flow, so although the amount of electrons flowing remains same, their rate of flow decreases, so isn't the current supposed to be reduced rather than remain constant?   I could be totally wrong but I haven't  found any resource which gives me the answer to my question, everyone claims the amount of electron remains same (I agree) but no one refers to its rate. I am studying this entire chapter by myself so sorry if something I said tends to be wrong.


Every Function in a Finite Field is a Polynomial Function

From a bank of past master's exams I am going through:     Let $F$ be a finite field. Show that any function from $F$ to $F$ is a polynomial function.   I know that finite fields are fields of $p$ elements for $p$ prime [EDIT: It's actually $p^n$ for $p$ prime; see comment below]. Since I have $p$ choices for the $p$ elements to map to, then I have $p^p$ distinct functions. I think every function can be written in the form $f(x) = a_{p-1}x^{p-1} + \dots + a_0x^0$. For then given the values $f(0), f(1), \ldots f(p-1)$, I can solve for the coefficents by the linear system of equations  $$ a_0 + \sum_{i=1}^{p-1} n^i a_i = f(n).$$  This then gives me a $p-1 \times p-1$ square matrix over the field $\mathbb{F}_p$:  $$\left( \begin{array}{ccccc} 1& 0 & 0 & \ldots & 0 \\ 1& 1 & 1 & \dots & 1 \\ 1& 2 & 4 & \dots & 2^{p-1} \\ \vdots & \vdots & \vdots & & \vdots \\ 1 & p-1 & (p-1)^2 & \dots & (p-1)^{p-1} \end{array} \right) \left( \begin{array}{c} a_0 \\ a_1 \\ a_2 \\ \vdots \\ a_{p-1} \end{array}\right)  = \left( \begin{array}{c} f(0) \\ f(1) \\ f(2) \\ \vdots \\ f(p-1) \end{array} \right)$$  If I can show this matrix is invertible, then I can always find the $a_i$. But I am a bit stumped on how to show this (partially because I don't think I've ever done linear algebra in a vector space over a finite field). It does not seem easy to show linear independence, or nonzero determinant, or full row rank.    Alternatively (I just thought of this), can I show this is true by arguing that the map between the two sets (the set of polynomials of degree $p-1$; and the set of functions $F \to F$) is injective, and that it must be a bijection because the sets have the same cardinality $p^p$?


View shell function's current definition

So I am editing bashrc constantly, and I have a terminal open with a working function definition, although bashrc has been updated with a wrong function definition. (Because the definition do not change until I source the updated bashrc) How can I look up the working function definition in this case? For example, if I type:  alias function_name   I can see what the definition is for that alias. Is there a command similar for function? If not, is there a command to output entire bashrc that the current terminal is using?


Problem installing phpmyadmin after upgrading to ubuntu 14.04

I've just upgraded from Ubuntu 12.04 to 14.04 and my phpmyadmin installation just vanished (I guess I did something wrong!). I've tried to reinstall it, but got this:  Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming.  The following information may help to resolve the situation:  The following packages have unmet dependencies: phpmyadmin : Depends: php but it is not installable              Depends: php-cli but it is not installable              Depends: php-mysql but it is not installable              Depends: php-json but it is not installable              Depends: php-mbstring but it is not installable              Depends: php-xml but it is not installable              Recommends: php-gd but it is not installable              Recommends: php-bz2 but it is not installable              Recommends: php-zip but it is not installable              Recommends: php-tcpdf but it is not going to be installed E: Unable to correct problems, you have held broken packages.   Any suggestion would be greatly appreciated.


How to add underbrace outside square root

I am trying to use latex to write the below. The code I have makes the underbrace contained in the square root so the square root symbol is larger, but I want it like it is in the bottom picture. This is what I have:    This is what I want:    Here is my code:  $ \sqrt{\underbrace{\overline{xx\cdots x}}_{2n}-         \underbrace{\overline{yy\cdots y}}_{n}}=   \underbrace{\overline{zz\cdots z}}_{n}$


Distribution of a difference of two Uniform random variables?

Let $X$ and $Y$ both be distributed between $[1,2]$, what is the distribution of $Z=X-Y$?


Prove that $f(x)=\sin x$ uniformly continuous on$(-\infty,\infty )$

Please check my proof   The original problem ask to determine sinx is uniformly continuous on$(-\infty, \infty )$ and if it is, Prove it   I think this function is uniformly continuous   Ok let do it .  Let $\epsilon ,\delta >0 $  $$|x-y|<\delta \rightarrow |f(x)-f(y)<\epsilon $$  $$     \rightarrow |sinx-siny|<\epsilon $$  Use identity  $$     \rightarrow |2cos(\frac{(x+y)}{2})sin(\frac{(x-y)}{2})|$$  $$     \rightarrow cos(\frac{(x+y)}{2})sin(\frac{(x-y)}{2})<\frac{\epsilon }{2}|$$  Choose $\delta =\frac{\epsilon }{2}$  then  $$ |x-y|<\delta \rightarrow 2|cos\frac{(x+y)}{2}sin\frac{(x-y)}{2}|<2\frac{\epsilon }{2}|=\epsilon $$  Then the function is uniformly continuous on$(-\infty ,\infty )$


How can I split the following string to an array of {"George", "Washington"};  String arr = "George\nWashington";


How could I find $x$ in this equation $x^2-x+6 \equiv 0 \pmod {9}$

This equation is like this: $$x^2-x+6 \equiv 0 \pmod{9}$$  I want to find x by using modular arithmetic. How I could do that?   My solution was:     $$\begin{align*}  x(x-1) &\equiv -6 \pmod{9}\\ x(x-1) &\equiv 3 \pmod{9} \end{align*}$$      So $x$ is either:   $$ x \equiv 3\pmod{9}$$      or       $$x - 1 \equiv 3 \pmod{9}$$      Which is $x \equiv 4 \pmod{9}$   I know what I have done is very dumb. So what is the correct solution? Give me the instructions also please.


Finding the maximum likelihood estimator

Find the MLE of the unknown parameter $\theta$ when $X_1,X_2,...,X_n$ is a sample from the distribution whose density function is: $$f_X(x) = \frac12e^{-|x-\theta|}, -\infty<x<\infty$$ What I did so far: $$\text{maximize }(\frac12)^ne^{-|x_1-\theta|-|x_2-\theta|-...-|x_n-\theta|} \\ \text{thus we want to minimize }|x_1-\theta|+|x_2-\theta|+...+|x_n-\theta|$$ Since $|x_i-\theta|$ is positive for all $i$, we want to solve for $\theta$ so: $$|x_1-\theta|+|x_2-\theta|+...+|x_n-\theta|=0$$ What do I do from here?


I would like to set up an APT repository on a server that will provide a couple of packages.  Is there a way to set one up without installing any software on the server?  How do the files have to be organized?    Edit: I must be doing something wrong... can someone please help me? I have the repository at   I'm not sure where or what, but something's misconfigured. I only currently have one package and it's for all architectures.  Here's what's been added to my /etc/apt/sources.list:  deb http://quickmediasolutions.com/apt stable main


How useful is that rule and how many times we can use that in one game?  Under what conditions can the en passant rule be used?  How often does it come up and is it a good idea to use it?


Should I delete my answer if it is inferior to another answer?

I recently , and I must admit that another user posted an answer superior to mine.  Although my answer is correct, I thought about deleting it. What is the suggested behavior?  Should I leave it and simply be a good sportsman by upvoting the other answer? Should I delete my answer so that further viewers only see the best solution?


Regarding travelling in and out of the US. I am on a J-1 visa and wish to go to The Bahamas in my grace period.    If I want to return to the US after The Bahamas I know that I cannot enter on my visa but can I enter on an ESTA instead?


jersey ResponseBuilder filename encoding

In javax.ws.rs.core.Response.ResponseBuilder, when I set filename, with polish (german, french, etc.) national characters, it changes file name before response is sent to client:  ResponseBuilder response = Response.ok(file); response.header("Content-Disposition", "attachment; filename=żółty.txt");   After this, file is being downloaded as "-óBty.txt". How to fix this?  EDIT: Whole application works properly with UTF-8 (json content contains polish characters for example). Only http headers doesn't.


Space opera about two humanoid races at war.

I read the subject book in 1981 and it wasn't new then. The book probably would be described today as a space opera.  From what I can remember there is an intersolar system war between two solar system races NOTE humanoid, not human. One planet is eventually destroyed  (the asteroid belt) and the other is laid waste...  There is a colony on the dark side of the moon that is destroyed in a massive meteor storm with the survivors walking to rescue on the moons surface gradually dying off until only # one makes it through sheer bloody minded determination to the rescue site where a small number of survivors revamp to earth Now the story swaps back and forwards with many reverses and twists but in the end archaeologists find the one walkers equipment buried for over 2000 yrs...aka  our forefathers..  And that's what I can remember, the story is intense and the revelations during the book are stunning I seem to remember.


14.04, Gnome Flashback desktop. How to create desktop shortcut for Firefox or other applications? Preferably, without installing additional components.


How to use the elements in array method into main?

I want to use the elements of array comNumber, in ranNumber() method but when I using this in main() it only shows the address of array. How can I fix this problem?      public class BaseballGame {     public static void main(String[] args) {         BaseballGame bGame = new BaseballGame();         System.out.println(bGame.ranNumber());       }      public int[] ranNumber() {         Random rand = new Random();         int[] comNumber = new int[3];         for(int i=0; i<comNumber.length; i++) {             comNumber[i] = rand.nextInt(10);             for(int j=0; j<i; j++) {                 if (comNumber[i] == comNumber[j]) {                     i--;                     break;                 }             }         }         return comNumber;     } }


Is it possible to see python codes even after converted to .exe?

Is really possible to find or see codes of a .exe program written whit python?   If yes what should do to protect program?  Thanks


How to disable manual input for JQuery UI Datepicker field?

I decided to use the JQuery UI Datepicker script for picking dates. Below is part of my code, and the way I integrated it into my PHP page:  <link type="text/css" href="css/south-street/jquery-ui-1.8.6.custom.css" rel="stylesheet" />      And:      // date picker (embeds JQuery script) echo 'Date: '; echo '<input type="text" name="datepicker" id="datepicker" />'; echo '

';   Pretty much according to the JQuery UI instructions.  Now my question is: how can I disable manual inputs in the text input field? I only want the JQuery Datepicker script to be able to fill the text field. As far as I can see, the script currently prevents the user from entering any non-numerical characters into the text field, but any combination of numbers is allowed (therefore, gibberish like "95460829468" is allowed).


Wifi not working for Lenovo Ideapad 330 with Rayzen 3 and RTL8821CE wifi drivers

I tried all option whatever is available whether it's for lenovo or Hp but my wifi is not working on my laptop neither is it working on Ubuntu mounted on vm or installed as dual boot with Windows 10.  My secure boot is disabled and OS is loaded in UEFI mode.  I tried both 18.04 and 19.04 version of Ubuntu but same result   I tried the option given here as answer but it didn't work at all.


How to Install "not installable" dependencies?

I'm trying to install Codelite on Ubuntu Artful (17.10). I've seen this problem is very common online but I haven't found a fix. Basically when I run sudo apt-get install codelite wxcrafter I get these unmet dependencies  Reading package lists... Done Building dependency tree        Reading state information... Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation:  The following packages have unmet dependencies:  codelite : Depends: libclang1-3.6 (>= 3.2) but it is not installable             Depends: libhunspell-1.3-0 (>= 1.3.3) but it is not installable             Depends: liblldb-3.6 but it is not installable             Recommends: lldb (>= 3.4) but it is not going to be installed             Recommends: nodejs but it is not going to be installed E: Unable to correct problems, you have held broken packages.   Now I've tried to manually install Artful versions of the dependencies (such as ) but the error remains there. I'm kind of a noob on these sort of things. Is there anyway to like manually install a dependency? (from like a downloaded file?) Or is there any sort of fix to this?  Thank you very much!  Edit: I don't think it's the same as the the question this is marked as duplicate: that's about clashing dependencies this is about missing ones!


Is there a way to identify the number of screens using javascript or jquery?  We have an application which should not be mirrored on any screen, even the case hardware supporting more than one screen.  Thanks in advance.


I'm trying to calculate the following determinant: $$\begin{vmatrix} a_0 & a_1 & a_2 & \dots & a_n \\ a_0 & x & a_2 & \dots & a_n \\ a_0 & a_1 & x & \dots & a_n \\ \dots & \dots & \dots & \dots & \dots \\ a_0 & a_1 & a_2 & \dots & x \end{vmatrix} = $$ $$ = \begin{vmatrix} a_0 & a_1 & a_2 & \dots & a_n \\ a_0 & a_1 & a_2 & \dots & a_n \\ a_0 & a_1 & a_2 & \dots & a_n \\ \dots & \dots & \dots & \dots & \dots \\ a_0 & a_1 & a_2 & \dots & a_n \end{vmatrix} + \begin{vmatrix} 0 & 0 & 0 & \dots & 0 \\ 0 & x - a_1 & 0 & \dots & 0 \\ 0 & 0 & x - a_2 & \dots & 0 \\ \dots & \dots & \dots & \dots & \dots \\ 0 & 0 & 0 & \dots & x-a_n \end{vmatrix} = 0 + 0 = 0 $$  Still, experimental results contradict, since for one example I get a non-zero determinant.  What am I doing wrong?


Extra Dimensions (in String Theory) - What does it mean?

I have been reading a lot about string theory and the necessity of extra dimensions (particularly as visualized in Calabi-Yau spaces), as "curling-ups" in our apparently 3-dimensional (or 4-dimensional, including time) world. I do not understand, though, how all these "extra dimensions" are actually adding dimensions to our world.  Even if these little multi-dimensional curls are everywhere and too tiny for us to see, how is it still adding extra dimensions? I mean, if our eyes were sharp enough, couldn't one still specify their location according to an $x,y,z$ axis? They will be a certain amount to the "left," a certain amount "high," and a certain amount front or backward (etc). It's still length, width and depth.   What am I missing here?


For example, rigid bodies and fluid. I know it's kind of possible by setting the rigid bodies as fluid obstacles, but it's not "true" interaction in that the fluid does not affect the rigid bodies...  By "true" interaction I mean where two (or more) physics systems affect each other simultaneously. For example, with rigid body and cloth, the rigid body affects the cloth but the cloth doesn't affect the rigid body (at least the way I'm doing it), so the rigid body just eventually stretches the cloth to an extreme and falls through...  Are there any ways to achieve this? (for any interaction, not just rigid bodies and fluid)  Or, if not, does anyone know whether there are any plans to implement this sort of feature?  Thanks


Virtualbox: How can I get a usable screen resolution inside the Guest OS

I have just installed the virtualbox application on my Ubuntu 14.04 OS (host OS). I then installed another Ubuntu 14.04 "inside" the VM i.e. the guest OS. The problem is the resolution is tiny and unusable and I need to increase the resolution "inside" the guest OS  here is what I have tried already  starting with a brand new install of Ubuntu 14.04 "inside" the VM  Install and configure the virtualbox guest additions   sudo apt-get install virtualbox-guest-additions-iso - (run from inside the guest OS) this seemed to attempt to modify/build kernel modules, and there were some failures. Then set x86 virtualization settings (again inside the guest OS)   Go to System settings → Software and Updates → Additional drivers Use x86 virtualization solutions... then reboot VirtualBox    Then what am I supposed to do - from there?  I have tried going into (from the host) virtualbox application -> file -> preferences -> display, then apply a "hint" of say 800x600. But when I start the virtual box the res. is still something like 640 x 480  If I go into the guest OS'es display settings - there is still no option  I have also googled for a solution and see there are answers, but they are outdated, give various solutions that dont work for me


Granting access to users to run specific SQL jobs that runs SSIS packages

We need to grant a couple of users access to run only specific SQL jobs that runs SSIS packages. Is there a solution that can be used to accomplish this?


How do I move window buttons to the right on Ubuntu 20?

After upgrade to Ubuntu 20, my window buttons moved again to the left and I don't know how change it in this version of distribution.


Are absolutely convergent sums exactly those which can be reordered?

If an infinite sum is absolutely convergent, its limit remains the same however the terms are permuted. Does a sequence of real numbers $(a_n)_{n\in\mathbb{N}}$ exist such that $\sum_n a_{\small P(n)}$ is the same for all permutations $P:\mathbb{N}\overset{\text{bijectively}}{\to}\mathbb{N}$, and such that $\sum_n |a_n|$ diverge?


Why does Windows' performance degrade over time even when it isn't used?

I know that similar questions have been asked before (like  and ), but none of them answer my question. My problem is, as stated in the title, that when Windows isn't in use (some months) its performance degrades. (Boot time goes from ½ minute to 2 minutes) If I boot Windows every day for a week, the boot time shrinks, but I have disabled defragmentation.  The other answers indicate that it might be fragmentation or bit rot. I know for sure that i can't be fragmentation since the hard drive is not use when not booting Windows (except for benchmarking from Linux). However, when benchmarking the drive under Linux (always booting from a separate drive), the drive's performance doesn't drop over time.  Edit: The computer I described in the question runs Windows 8, however I've also experienced this on Windows 7.


Can't get an access to jQuery in my scripts

Edited problem description I develop a theme for the Drupal 8. I need to have an access to jQuery $ context in my scripts, so I attached it in libraries as it says in docs.    global-styling:     version: VERSION     css:         theme:             libs/bootstrap/css/bootstrap.min.css: {}             css/layout.css: {}      js:         libs/bootstrap/js/bootstrap.min.js: {}         libs/autohiding-navbar/jquery.bootstrap-autohidingnavbar.js: {}         js/global.js: {}      dependencies:         - core/jquery   But in the Chrome console I get an error that jQuery context $ isn't available.


Wide figures to spill out into the outer, not inner, margin in double-sided documents

I'm writing a text where I have some figures that need to be wider than the text width, and I want then to spill out into the outer (in my text, rather wide) margin. I have tried a solution which I found in a previous question here, but I can't make it work.  I copied the code in   and modified it to:  \usepackage{ifoddpage}  \begin{figure}   \checkoddpage   \edef\side{\ifoddpage l\else r\fi}%   \makebox[\textwidth][\side]{\includegraphics[width=1.4\textwidth]{wide_image}}      \caption{xxx}   \label{fig:1} \end{figure}   This makes figures behave the correct way on odd pages (they are left-aligned with text), but not on even pages (where they are still left-aligned with the text, making them spill into the inner margin instead)?   I'm using the "report" class.


In C, is the condition : "if(a != NULL)" the same as the condition "if(a)"?

Let's say a is a pointer, and after allocating memory for it, I want to check if the memory was allocated successfully, I've seen two ways doing this :  if(a != NULL)  if(a)   What is the difference between the first and second statements ?


Why does a the addition of a total derivative to the Lagrangian leave the equations of motion invariant?

Take a Lagrangian $L \rightarrow L+\partial_{\mu}F^{\mu}$.  If we can show that the total derivative $\partial_{\mu}F^{\mu}$ identically satisfies the Euler-Largrange equation, then we have shown that the equations of motion will be unchanged.  How can we show this, even for the simple example of one space coordinate (and its time derivative)?


Why can't I get notifications on the questions I starred?

I don't know what the reason of existence of the star feature is, but intuitively I star questions to express interest in it.  I think it would be nice to be able to get notifications on the questions I've starred (=expressed interest in, in my understanding of the feature).


First it would be nice to search through the questions I've asked on SO to find a particular question.  Second, it would also be nice if the main search function at the top of the page had an "advanced search" option whereby you could specify things like tags and whether you're looking for answers or questions or both and perhaps specify a date-range.


I am Dutch citizien (EU) married to a US citizen. Can I travel to US to visit my husband during travel ban?

I have a valid ESTA and my husband lives in the U.S. and my immigration visa is in processing.


What happens when bear is not able to buy back the shares (to be more precise borrowed shares) he sold?

I came across the stock market jargons: Bull and Bear. A bit of research on bear helped me understand bear as the person who borrows shares/stocks with speculation that the price of the borrowed shares/stocks may fall in the future. So he/she basically borrows the shares and sells it, with an intention of buying back when the price of that stocks falls below the price at which they were sold. What happens when he/she is not able to buy back the shares, maybe because no one is willing to sell those shares.


I have and object1 with a unknown key name and i need to merge with other object2. The secure point is that unknown key is not present in the object2 so, never gonna be key names conflicts.  var object1 = {  id: 1,  name: "myname",  boleanSample : true }   var object2 = {  unknownKeyName : "UnknownValue" }   I want to merge object2 into object1 and get this  var object1 = {  id: 1,  name: "myname",  boleanSample : true,  unknownKeyName = "UnknownValue" }   Please, vanilla Javascript only. If the response require the creation of an new object3 is totally fine :)  PD: I checked these links before post the question:      ( uses arrays... )   ( Just for known keys, not useful for this case )  ( Bad post, no sense )   No duplication at all for those :)


Quoting / escaping / expansion issue in "command in a variable"

I want to run a command such as this in a bash script:  freebcp <authentication and other parameters> -t "," -r "\r\n"   When run directly on the command line, the command works as expected. But when placed in a variable in a bash script it returns an error such as this:  Msg 20104, Level 3 Unexpected EOF encountered in bcp datafile  Msg 20074, Level 11 Attempt to bulk copy an oversized row to the server  bcp copy in failed   When command is placed in a variable and double quotes are escaped:  cmd="freebcp ${db_name}.dbo.${table_name} in ${p_file} -S ${server_name} -U ${username} -P ${password} -t \",\" -r \"\r\n\" -c" `$cmd`   Note: Putting the following in the script works as expected:  `freebcp ${db_name}.dbo.${table_name} in ${p_file} -S ${server_name} -U ${username} -P ${password} -t "," -r "\r\n" -c`   So I know there's some quoting/escaping/expansion problems but I can't figure out how to fix it.  Note 2: Single quoting -t -r parameters doesn't work either


Logistic regression and balanced treatment groups

When using logistic regression how critical is to have balanced treatment groups. I have a binary response variable (pregnant and non-pregnant) from two treatments at n=40 and n=14? How does the need for balance compares to OLS analysis? Is there any published information on the subject?


I have both Ubuntu 18.04.5 LTS and Windows 10. I need some space for Ubuntu, so I wanted to transfer some disk space from Windows to Ubuntu. When I tried that, I have got a problem. For convenience, I added a picture. As seen in pic, I have got two parts:  the / mount point the /home directory  When I try to move my unallocated part, the "/" directory doesn't allow me. In a nutshell, how can I transfer my 35 GBs of space to Ubuntu?  Thanks for all your bits of help.


Comparing string in Android using if statement

Here I am trying to get txt from EditText field , and compare it with another string that I defined in the code, after the compare done I am gonna show some messages that sys " they are equal " just I wann use it for another purpose. I tried this code it prints what I write in the EditTex into TextView. but it did not compare i what I type in they r equal or not. Plz help            final Button btntx = (Button)findViewById(R.id.btn1);             final EditText edittxt1 = (EditText)findViewById(R.id.edttxt);             final TextView messageshow= (TextView)findViewById(R.id.txtview);                     btntx.setOnClickListener(new View.OnClickListener() {                 @Override                 public void onClick(View v) {                     Button b= (Button)v;                      String data= edittxt1.getText().toString();                     String takefromtost= "Turn on";                  messageshow.setText("  " + data);                  if (data=="Turn on")                     {   Toast.makeText(getBaseContext(),"They are equal", Toast.LENGTH_SHORT).show();                  messageshow.setText("They are equal");                      }                   }             });


Make .search() case insensitive for a variable

I'd like to make .search() case insensitive for a variable I've entered into it. From the documentation on W3 it appears I can only hard code case insensitive searches. The example on W3 goes:  var str = "Mr. Blue has a blue house"; var n = str.search(/blue/i);   My code looks like:  var searchTerm = $("input").val(); var source = $("#page5").html(); var found = source.search(searchTerm);   If I were to code it like the W3 example then the .search() command would look like:  var found = source.search(/searchTerm/i);   However, when I do that it appears to attempt to search for the literal text of "searchTerm" instead of the value within the variable searchTerm. Is there a way to use the case insensitivity on the search method while inserting a variable into it?


Como calcular el area de la superficie de un huevo con calculo

Estoy haciendo mi reciente evaluación interna del IB Matemáticas HL y mi tema es cómo calcular el área de superficie de un huevo . Quiero aplicar el cálculo conocimiento en esta pregunta, pero mi conocimiento sobre esta área es limitada. Sólo sé la información básica acerca de cálculo, por ejemplo, mediante la integración para calcular el volumen de un objeto. Ya he buscado información relevante en línea durante muchos días, pero todavía tengo ni idea.  Translation (slightly cleaned-up Google Translate): I am doing my recent internal assessment of the IB Math HL and my subject is how to calculate the surface area of an egg. I want to apply knowledge of calculus in this question, but my knowledge about this area is limited. I only know basic information about calculus, for example, by integrating to calculate the volume of an object. I have already searched for relevant information online for many days, but I still have no idea.


How can I install sudo without using su?

I need to use sudo but when I try to use it, a prompt tells me the command is not found and I need to install sudo. So when I switch to su so I can gain root access to install sudo, it says auth failure    How can I fix this?


Why does it seem like parts of my code is being skipped over?

I have a program in JAVA that I am working on. It uses recursion to count up based on the number entered. I'm using a while loop that loops if an error is thrown. I'm trying to code a feature that allows the user to continuously enter numbers until n/N is entered with a do/while loop. Here is my code so far:  public static void main(String[] args){     Scanner keyboard = new Scanner(System.in);      System.out.print("Enter a number: ");     String input;     input = keyboard.nextLine();             String again;     do{         while(true){             try{                 int number = Integer.parseInt(input);                 int base = 1;                 /*                   The countUp function is called from                   from my parent class SimpleRecursion.java                   which is where the recursion happens                 */                 countUp(base, number);                  break;                             }              catch(NumberFormatException e){                 System.out.print("Error invalid entry." + "\n" + "Enter a number: ");                 input = keyboard.nextLine();                 continue;             }         }          System.out.print("Again? y or n? ");         again = keyboard.nextLine();         if(again.equals("n") || again.equals("N"))             System.exit(0);     }while(again.equals("y") || again.equals("Y")); }   However, when the try block breaks out of the while loop it seems to end the program. I've tried labeling my do loop A and the while loop B and using "break B", to break out of the while loop but that did not work either. Also: my Scanner import is at the top of the parent class. I can post the entire file, the code would work fine for a single correct input and the program loops correctly if the NumberFormatException is thrown. Thanks.  EDIT: I changed again=="string" to again.equals("string") and the results were the same.  The problem was in my countUp function which looked like this:  public static void countUp(int x, int end){     if(x > end)         System.exit(0); // When the number reaches the number entered. The                          // program ended.      else{         System.out.print(x + "\n");         countUp((x+1), end);     } }


Answer with more upvotes appears above accepted answer?

The highest-voted answer on  has three votes, and appears above the accepted answer (two votes). I think it's an amusing coincidence that it just so happens to be a Jon Skeet answer. What's going on here? Shouldn't  be at the top?


Showing that $\mathsf{Cov}(f(X), g(Y)) \geq 0$ for non-decreasing $f$ and $g$ taking values on $\mathbb{R}$.

We have two non-decreasing functions $f$ and $g$ and a random variable $X$. We want to show that $\mathsf {Cov}(f(X),g(X))\geqslant 0$.   Intuitively, it makes sense, but how do I formalize this?


Javascript: order of "for" cycle through object props

If I have an object an cycle through its properties:  var obj = {a: 1, b: 2, c: 3}  for (var prop in obj){    console.log(obj[prop]) }   Will I inevitably always get: 1, 2, 3 as a result? On what it may depend? Is other result practically real?


How to keep special characters(āēīōūĀĒĪŌŪ) in php and avoid them converting?Please do not mark as duplicate

How I can keep following characters in my paragraphs and stop them being converted or replaced by ' ' empty one or ? marks. I am trying to save following paragraph: "Nā Tā Tīmoti Kāretū a He Muka i tīmata hei pānui reo Māori anake mā te marea. Pānuihia āna kōrero mō te take i whakaterea te pānui toru tekau tau ki muri."  it's Maori language and I wanted to keep it into my database table without converting them to following. "N T Tmoti Kret a He Muka i tmata hei pnui reo Mori anake m te marea. Pnuihia na krero m te take i whakaterea te pnui�toru tekau tau ki muri."  I am using following code to detect if the paragraph have this type of special maori keywords or not.  $keywords = 'āēīōūĀĒĪŌŪ';             $keywords_array = array('ā','ē','ī','ō','ū','Ā','Ē','Ī','Ō','Ū');              for($i=0;$i<count($keywords_array);$i++) {                 if(strpos(str_replace(" ","",$_POST['editor1']), $keywords_array[$i]) !== false) {                     $found = true;                 }             }             if($found) {                 //found one possiblities....keep as it is the paragraph but storing into database like other paragraph:(                 $output = $_POST['editor1'];                     }   Can anyone tell me how I can stop converting special characters when storing in php mysql database.  Please let me know any solution as now it's quite long that I couldn't find simple solution. thanks


I have searched but apparently my google foo is weak. What I need is a way to prompt for user input in the console and have the request time out after a period of time and continue executing the script if no input comes in. As near as I can tell, Read-Host does not provide this functionality. Neither does $host.UI.PromptForChoice() nor does $host.UI.RawUI.ReadKey(). Thanks in advance for any pointers.  EDIT: Much thanks to Lars Truijens for finding the answer. I have taken the code that he pointed out and encapsulated it into a function. Note that the way that I have implemented it means there could be up to one second of delay between when the user hits a key and when script execution continues.  function Pause-Host {     param(             $Delay = 1          )     $counter = 0;     While(!$host.UI.RawUI.KeyAvailable -and ($counter++ -lt $Delay))     {         [Threading.Thread]::Sleep(1000)     } }


When should I use "while" and when should I use "whilst"?

I was curious as to the correct uses of the words "whilst" and "while". In what context should I use them?


Can I say "Our school rugby team is good"? or should I say "Our school's rugby team is good?" Is there a difference?


How to open a program and make it run on the currently open console app in C++

I was wondering if there is any possible way to make a console application open in the parent console. Like how MS-DOS opens the app when you type something like <path_to_file>\<filename>.exe, it doesn't close the CMD window, it just opens the app you typed the name for in the current window.  I need to do this in C++, without using system(), as everyone knows about the security risks etc.  I tried CreateProcess() but that opened another window. I am not worried about portability, this is a Windows only application anyways.


Does SE have a site for psychology questions?

I'm not sure if it exists or not, but does Stack Exchange have a site for asking psychology questions? And if not, is it possible to create one?


I'm looking for the Book that explains the essentials of user interface and user experience design.   I read  and  from O'Reilly. I think they are very good but, I'm still looking for the one.  Please provide your recommendation and why it stands as the essential reference.


Is the current version of Ubuntu usable on a PPC mac?  I've got a "lamp shade" mac from 2003 that I'd like to recycle into my first Linux computer.  I'm not a programmer.  So it appeals to me that Ubuntu is a download/upload kind of thing.  Apple iMac G4 1.25GHz  Any suggestions?


$p=2^n+1$. Prove that every quadratic nonresidue modulo $p$ is a primitive root modulo $p$

This is another one of the number theory problems I've been struggling with as of late (hopefully I'm not posting too many questions at once!).     Let $n$ be a positive integer and let $p=2^n+1$ be a prime number.   Prove that every quadratic nonresidue modulo $p$ is a primitive root   modulo $p$.   Suppose $a$ is a quadratic nonresidue and $r$ a primitive root muodulo $p$. Then there exists no $x$ such that $x^2 \equiv a \mod p$. We must determine the order of $a$. We know that $a$ must be congruent to some power of $r$, say $m$, since $\{r^1,r^2,\ldots,r^{2^n}\}$ is a reduced residue system modulo $p$. Suppose that $\mathrm{ord}_p a=b$. Then $a^b \equiv r^{mb} \equiv 1 \mod p$. We must show that $b=2^n$ since $\phi(p)=2n$. But $r$ is a primitive root and so $mb \equiv 0 \mod{2^n}$ (or $\equiv 2^n \mod{2^n}$). Hence $mb = 2^n k$. How can I finish it?


Is it possible to use the mic and headphone simultaniously when using a2dp? the sound quality is really bad when using hsp/hfp.


Click Event Does Not Work When Dynamically Adding a Column in Javascript

I am dynamically adding a column via jquery:  $('#id_orderTable tr:last').after('
' +  orderLine.short_desc + '	<input type="button" value="-" class="qtyminus"></input>	'   I have a listener for "qytminus"   $('.qtyminus').click(function(e) { ... some code...}   If I just write the code on a predefined table, the onclick triggers just fine and ...some code... is executed.  However when I click on the button when I add the row dynamically, the onclick does not get invoked.  Is this even possible with dynamic content additon?


Wordpress Custom Theme: My site shows the same posts on Page 1 and Page 2 and so on

Despite the pagination going to nieuws/page/2, it still shows the same posts as on the first page. This is my PHP code for the blog:

Laatste Nieuws

                        <?php         $args = array(           'post_type' => 'nutrisense_nieuws'         );          $the_query = new WP_Query($args);        ?>        <?php if ($the_query->have_posts() ): while ($the_query->have_posts() ) :$the_query->the_post(); ?>

<a class="post-title" href="<?php  the_permalink(); ?>".><?php the_title(); ?>

<?php the_time('j F, Y'); ?>

<?php the_post_thumbnail(); ?>

<?php the_excerpt(); ?>

<a class="post-title" href="<?php  the_permalink(); ?>".>Lees meer..
         <?php endwhile;?>         <?php         previous_posts_link('&laquo; Nieuwere berichten');         next_posts_link( 'Oudere berichten &raquo;', $the_query->max_num_pages );         wp_reset_postdata();         ?>          <?php endif; ?>


FreeDOS USB drive does not show in option key boot menu on Macbook Pro (Late 2011)

I've been struggling for two days to dual-boot FreeDOS along with Mac OS X on an old MacBook (late 2011)  that I have.    I've tried doing the live CD option and flashing it to the drive with Rufus. I've tried following the instructions on the FreeDOS website for the USB drive and copying the contents of the .img file to the disk. and I've tried using Boot Camp which gives me an error that the Windows installer isn't found.   Nothing works. Does anyone have any idea of what is going on?


raise window underneath the current active one

I am wondering is there a shortcut to raise another app's window underneath the current app's active one, so i can quickly toggle the top two windows, as this is a common workflow in my daily work.  I have tried a few window management apps, but couldn't find any that allows me to do this task.  I want to bring the window upfront immediately, not something like Command + Tab that goes through a list of all open windows.


How does Solenoid works? How do I calculate its output power?

Here is a solenoid valve. It is a normally closed, which is mean, it is normally closed the valve. Vice versa, there is also normally open, which is mean, it is normally open the valve until it supplied with electric power to pull the rod. This type of solenoid available DC and AC current source.  What my concern here are how it work? How do I calculate its power requirement (Voltage, current), and its output power to force or to pull the rod so it close or open the valve as I explained above. What should be calculate here, is it B (magnetic field), or F (force)? And how to calculate it?


How can I see the result of an animated texture in the viewport?

I am animating the textures of a model, but when I scrub through the frame timeline the texture is displayed as a still image. I am making an animation were the textures are of eyes and they keyframe different textures to perform a blinking animation, but the only way I can see it is when I render the animation. How do I see the texture keyframes while scrubbing through the timeline instead of them appearing as still images?


Lagrangians with higher derivatives than Klein-Gordon

Has anyone ever tried to work with Lagrangians involving higher derivatives?  The Klein-Gordon Lagrangian only involves $(\frac{\partial}{\partial t})^2$ and $\nabla^2$ terms, what about third and higher derivatives?  What is so special about the Klein Gordon field anyway?


TikZ: is there a better way to represent the following node content

Consider the code below:  \documentclass[convert = false, border = 1cm]{standalone} \usepackage{tikz} \begin{document} \begin{tikzpicture}   \node[font = \scriptsize] at (-3.5, 4) {Position of $S_2$ when};   \node[font = \scriptsize] at (-3.5, 3.7) {$S_1$ reaches $C$}; \end{tikzpicture} \end{document}   I used two nodes to write short explanation of a point in a figure I am constructing.  However, I had to play around with the set up so they weren't spaced vertically too far a part and the second node was centered on the content of the first node.  Is there a better way to this?


Which of the following sets are compact in $\mathbb{M}_n(\mathbb{R})$[NBHM_PhD Screening Test-2013, Topology]

Which of the following sets are compact in $\mathbb{M}_n(\mathbb{R})$ (a) The set of all upper triangular matrices all of whose eigenvalues satisfy $|\lambda|≤2 $. (b) The set of all real symmetric matrices all of whose eigenvalues satisfy $|\lambda|≤2 $. (c) The set of all diagonalizable matrices all of whose eigenvalues satisfy $|\lambda|≤2 $.  (a) & (c) are not true. But I am not sure about (b).can anybody help me please.


Arbitrary/Infinite precision variables - C#

Is there any type in C#that would allow me to store a fractional number with arbitrary or infinite precision? I don't want to use any external libraries--would I have to write a class myself? How would I do this?  I need a variable to which I can apply the standard arithmetic operations, and get the result with as much precision as I want, something in which I could do something like calculate pi or another irrational number to a precision like 10,000 digits...


I'm thinking of picking up the book called "Killer Game Programming" by Andrew Davidson, but its pretty old, now. I know Java, and I've been messing with jMonkeyEngine for a few days, but I'm curious to see if I would benefit from the 3D chapters of this book.   The book was published was in 2005. Has Java changed to the point where this book would now be obsolete, assuming it was up to date at time of publication?


Is quoting a book in a question or answer copyright violation?

I read a book that answers one of my questions, and I would like to quote it as an answer. Is that illegal?    Thanks.


Distribution of Dark Matter around galaxies

It is well-known that measurements of the velocity profile in galaxies are not compatible with Newtonian laws. A way to circumvent the problem is to assume that galaxies are surrounded by a spherical halo of Dark Matter. The density of mass of this Dark Matter can then be computed from the velocity profile with Newton's laws.   My question is the following: the formation of a galaxy involves essentially only the gravitational interaction. According to Newton (and General Relativity too), the trajectory of a particle does not depend on its mass. As a consequence, I do not understand how usual matter and Dark Matter could have followed different trajectories leading to such different mass distributions nowadays. Can somebody explain this (apparent) paradox ?


Can't scroll through the starred messages in the chatrooms

When I hit on the show 9 more (or with whatever number), the container expands but goes behind the footer.  Here's a snapshot (from the JavaScript room):    This screenshot is taken on a 1440x900 resolution screen. As you can see, the scrollbar is way off.  (It seems more of a CSS issue to me.)


Why is a different dll produced after a clean build, with no code changes?

When I do a clean build my C# project, the produced dll is different then the previously built one (which I saved separately). No code changes were made, just clean and rebuild.   Diff shows some bytes in the DLL have changes -- few near the beginning and few near the end, but I can't figure out what these represent. Does anybody have insights on why this is happening and how to prevent it?   This is using Visual Studio 2005 / WinForms.  Update: Not using automatic version incrementing, or signing the assembly. If it's a timestamp of some sort, how to I prevent VS from writing it?   Update: After looking in Ildasm/diff, it seems like the following items are different:   Two bytes in PE header at the start of the file. <PrivateImplementationDetails>{guid} section  Cryptic part of the string table near the end (wonder why, I did not change the strings) Parts of assembly info at the end of file.   No idea how to eliminate any of these, if at all possible...


Checking connectivity of adjacency matrix

What do you think is the most efficient algorithm for checking whether a graph represented by an adjacency matrix is connected? In my case I'm also given the weights of each edge.   There is another question very similar to mine:   That answer seems to be good, except I don't really understand it. How does repeatedly squaring the matrix give information about its connectivity? There is another an answer that claims eigenvectors also give information about the connectivity of the graph, could anyone explain that as well?   I'm asking this because I don't have the background to understand the answers given, I'm just solving a problem that has to do with these topics. Searching around on google didn't give me an answer either, so hopefully someone can clear it up.


How can I put two figures side-by-side? Not two sub-figures, but two actual figures with separate "Fig.: bla bla" captions.  A figure is supposed to spread over the entire text width, but I have two figures which are narrow and long, and I need to save the space in order to withstand the pages limit.


How to implement WordPress in a subdirectory, hosted on a different server?

I am working with a client who already has a custom e-commerce website set up at their own domain e.g. example.com  We want to host their WordPress blog at a subdirectory of their domain e.g. example.com/blog Due to security issues we cannot host WordPress on the same server as the rest of their site.  We have set up a separate server which will host the WordPress blog, and given it a temporary subdomain URL.  How do we make it so that example.com/blog will serve the Wordpress site from our server? We don't want a redirect, we want it to appear as if all of the blog is hosted within the '/blog' subdirectory. What URLs do we put in the WordPress database? How should they be redirecting their subdirectory?  I know people recommend using a subdomain (this is what we currently have), but the client has specifically requested using a subdirectory for better SEO performance.


Can we use the command "sed" to replace a string to another string that includes the character " / "?

I try to replace "_" to "/"  $ echo "hahahaa_the_cat_hahahaa" | sed "s/_///g"   It doesn't work.


I'm doing subtitles for some videos on Youtube. I heard the words either and neither spoken in two different ways by the same person. Written it could be:      ee-ther versus i-ther or n-ee-ther versus n-i-ther   Is there a rule for which pronunciation to use? Or is it just a matter of birth/taste/location?


Return only the portion of a line after a matching pattern

So pulling open a file with cat and then using grep to get matching lines only gets me so far when I am working with the particular log set that I am dealing with. It need a way to match lines to a pattern, but only to return the portion of the line after the match. The portion before and after the match will consistently vary. I have played with using sed or awk, but have not been able to figure out how to filter the line to either delete the part before the match, or just return the part after the match, either will work. This is an example of a line that I need to filter:  2011-11-07T05:37:43-08:00 <0.4> isi-udb5-ash4-1(id1) /boot/kernel.amd64/kernel: [gmp_info.c:1758](pid 40370="kt: gmp-drive-updat")(tid=100872) new group: <15,1773>: { 1:0-25,27-34,37-38, 2:0-33,35-36, 3:0-35, 4:0-9,11-14,16-32,34-38, 5:0-35, 6:0-15,17-36, 7:0-16,18-36, 8:0-14,16-32,34-36, 9:0-10,12-36, 10-11:0-35, 12:0-5,7-30,32-35, 13-19:0-35, 20:0,2-35, down: 8:15, soft_failed: 1:27, 8:15, stalled: 12:6,31, 20:1 }   The portion I need is everything after "stalled".  The background behind this is that I can find out how often something stalls:  cat messages | grep stalled | wc -l   What I need to do is find out how many times a certain node has stalled (indicated by the portion before each colon after "stalled". If I just grep for that (ie 20:) it may return lines that have soft fails, but no stalls, which doesn't help me. I need to filter only the stalled portion so I can then grep for a specific node out of those that have stalled.  For all intents and purposes, this is a freebsd system with standard GNU core utils, but I cannot install anything extra to assist.


I was trying to install EPrints on my Ubuntu 20.04 desktop but it lacked the dependency package xpdf. I have tried multiple ways to install it but failed.  Could anyone please tell me how to install it .


How can I list permissions of every component in a file path?

Sometimes it is necessary to determine on which directory in a path access rights are limited. Here is an example:  $ ls /sys/kernel/debug/usb/devices ls: cannot access /sys/kernel/debug/usb/devices: Permission denied $ cat /sys/kernel/debug/usb/devices cat: /sys/kernel/debug/usb/devices: Permission denied   Neither ls nor cat shows where the user rights were limited.  What is the simplest way of showing the access rights for every component (directory and the file) in the path? I am mainly interested in solutions for Unix-like systems.


Can I customize how file information is displayed in Finder

There are 3 things I need from Finder for my work: I need finder to be in "Columns" view, I need the window to be relatively small, and I need to be able to see the "date modified" and "file size" in the preview pane. Since upgrading to Catalina, the icon image in the preview pane has gotten so big that I can't see any of the file information without scrolling - I've cropped the image but you can see how the file information isn't visible. I found out how to get rid of the "more" section underneath, but I still can't see the file information without scrolling.  I've tried going to View > Show View Options > Unclicking "Show Icon Previews", but that doesn't do anything. Basically I'd like for the preview image to be much smaller, or for the file information to show up on top. Here's an example of how it used to look where all the preview info was compact - this is how I'd like it to look in Catalina:


An 8 bit value can range anything from 0 to 255 in decimal, or 00 to FF in hexadecimal. But why did they choose 8 bits for the byte, out of all of the powers of 2 they could have chosen? Even still, a nybble seems like a more suitable value for the smallest addressable memory unit, because it takes only one hexadecimal digit to write down. The main downside with nybbles though, is that they will require double the fetch cycles to execute properly. But in that case, why not just make the byte length equal to the word length, requiring only one fetch cycle per instruction? And if its so useful for a byte to be 8 bits, what is its use in microprocessors that aren't 8-bit? This could really help me out in designing my first Logisim CPU, so why are bytes 8 bits, and what is the use of an 8-bit value in non-8-bit computers?


Proper term for people from eastern Asia

I once posted an article on the web in which I referred collectively to people from China, Japan, and the Koreas as "Oriental". I got an email from someone who informed me that this is an offensive term and that I should call such people by the specific country of origin -- "Chinese" or whatever -- or collectively as "Asians". She claimed that "Oriental" refers to an object, like "an Oriental vase", and is insulting when applied to a person.  I consider "Asian" inappropriate as it would include Siberians, Afghans, Pakistanis, etc. And of course "Chinese" is unacceptable if you want to include Japanese, Koreans, and related cultures.  So my question is: Do people from this part of the world really find the word "Oriental" offensive? If so, what term do they prefer for themselves? I'd be particularly interested in hearing from someone who actually is of Japanese, Chinese, etc., background, rather than an American or European saying what he thinks someone else thinks.  (Frankly I thought the argument about "Oriental" applying to an object was a little curious. I call myself an "American". I don't find it at all offensive that the same word used to describe me as a human being is also used to describe objects, like "American cars", "American food", etc. Both people and objects can be from the same physical place, so I don't see any problem with using the same adjective to describe both. But maybe there are different connotations to the word "Oriental". )


Drawing tools to add circles, arrows, lines for QGIS?

I'm pretty new in QGIS and i'm searching a drawing tool like it is possible to find in microsoft word or excel.  I search something very user friendly (for dummies!) to add circles, arrows, lines... with no need to create a new layer!!  Can you help me?


what is causing this error "UserAgent not available, file operations may not be optimized. "

I am working on an enterprise wiki site collection inside SharePoint 2013, and sometimes especially when modifying the wiki page name , users will get the following exception :-    I checked the logs and i find the following error "UserAgent not available, file operations may not be optimized. ... ". so can anyone adivce on this please? Thanks  Edit   Here is the log file uploaded to onedrive after enabling verbose logging , correlation id = 4bce009d-3c69-c0b7-30fc-0153080d3219 :-    i found the following 2 exceptions inside the log file :-   04/27/2015 12:51:36.38*   w3wp.exe (0x4640)                           0x225C  SharePoint Foundation           Files                           ak8dj   High        ...ecutionStep.Execute()     at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)     at System.Web.HttpApplication.PipelineStepManager.ResumeSteps(Exception error)     at System.Web.HttpApplication.BeginProcessRequestNotification(HttpContext context, AsyncCallback cb)     at System.Web.HttpRuntime.ProcessRequestNotificationPrivate(IIS7WorkerRequest wr, HttpContext context)     at System.Web.Hosting.PipelineRuntime.ProcessRequestNotificationHelper(IntPtr rootedObjectsPointer, IntPtr nativeRequestContext, IntPtr moduleData, Int32 flags)     at System.Web.Hosting.PipelineRuntime.ProcessRequestNotification(IntPtr rootedObjectsPointer, IntPtr nativeRequestContext, IntPtr moduleData, Int32 flags)     at System.Web.Hosting.UnsafeIISMethods.MgdIndicateCompl...  4bce009d-3c69-c0b7-30fc-0153080d3219 04/27/2015 12:51:36.49    w3wp.exe (0x4640)                           0x225C  SharePoint Foundation           Runtime                         tkau    Unexpected  System.NullReferenceException: Object reference not set to an instance of an object.    at Microsoft.SharePoint.Publishing.WssObjectCache.RemoveItemFromCache(Guid webId, Guid itemGuid, Boolean isList)     at Microsoft.SharePoint.Publishing.WssObjectCache.HandleChanges(SPChangeCollection changes)     at Microsoft.SharePoint.Publishing.CacheManager.CheckForChanges(SPSite site, Boolean forceGetChanges)     at Microsoft.SharePoint.Publishing.CacheManager.GetManager(SPSite site, Boolean useContextSite, Boolean allowContextSiteOptimization, Boolean refreshIfNoContext)


Interpreting coefficients in Linear Regression Y|X1, X2, X3

I am trying to reconcile an apparent contradiction in the results of my regression against three independent variables  $X_1,X_2, X_3 $:  1) For each of the $X_i's$, I regressed  $Y|X_i $ and in every case,the slope coefficient $b_i$ in $Y= b_0+b_iX_i$ was negative.  2) When I regressed $Y|X_1, X_2, X_3 $, only two of the (non-constant, i.e., not including $b_0$ ) $b_i$ coefficients came out negative.  But don't we interpret these $b_i's$ to mean that a change in one unit in   in $X_i$ in $Y=b_0+b_1X_1+b_2X_2+b_3X_3$ , while holding other $X_i$ to be zero, leads to a change in $b_i$ units of output in $Y$, apparently contradicting 1) ?   Also, shouldn't the coefficients in $Y= b_0+ b_1X_1+ b_2X_2+ b_3X_3$ equal to Cov(Y,x_i) , or does this last require that the $X_i's$ are standardized ( so that we would have $b_0=0$, so that the standardized coefficients should all be negative in order to agree with the condition in 1)?  Thanks.


Why is asking a question often the best way to find a question?

Possible Duplicate:          The following series of events happened to me today for about the 100th time:   I have a programming question I cannot answer. I search Stackoverflow for the right question and hope it has good answers. Finding none, I google, which often yields better stackoverflow hits (related: why is that?). I think more about the question, rephrase it, and repeat the above steps. Finally, I click "Ask Question" on the stack, and type the title for my question. Upon tabbing from the title, I find my question in the "Related Questions" section!   While this is a happy moment, I can't help but think that one of my six or seven searches should have found it for me. Has anyone else had the same experience?


Triggered by an interesting but speculative and open-ended discussion , I want to ask what the meaning of research is/was according to its etymological history. Maybe the knowledge here and wizard-like tools like ngram can shed more light on this question, at least I would like to see how people interpret/vote research. Please do not just simply reword different theories in this blog article, but add some traceable clues or a analysis how the meaning of the word changed gradually.


Search either misses some questions or they are incorrectly sorted in the active and newest tabs

On some sites, several searches that I tried after after choosing active tab or newest tab, the search only show questions at least 2 days old.   If I search for some extremely common word - for example limit on Mathematics site - at the top of the  and the  questions with last activity/creation day at least two days ago are shown.  Below are screenshots from Mathematics. I have noticed the same behavior on several other sites. (Although on  and  the search worked as expected - some relatively new questions were shown among the results.)  This is what I get in the active tab.    And this is the newest tab.    Browsing among questions tagged limits you can see many question that should have been displayed in the  and  of the above searches (and are newer than 2 days).


Finding additions and updates between two vector layers using QGIS

I am using QGIS. I have two exports of vector data created some 6 months apart. How do I find any new objects added in the 6 months, and any attribute changes in the original objects? An asset_id field exists in both tables as a unique identifier, and will carry through both tables. I can use the "Difference" tool to get geometry changes but can't get the attribute table changes too.


Is there any disadvantage to selling a Bobblehead or a magazine in Fallout 4?

In Fallout 4 the Bobbleheads are back.  Once you pick them up they stay in your inventory with a weight of 0 and a value of 300. Will I need them later ? Do I lose the bonus if I sell them or drop them somewhere ? Same with the magazines.  Is there any disadvantage to selling them ?


Let $M$ be a compact metric space and $F:M\to M$ be a function that preserves distances, prove that is an homeomorphism

If $(M, d)$ is a metric space, $M$ is compact and $F: M\to M$ preserves distances (that is to say, $d(x,y)=d(F(x),F(y)) \ \forall x,y\in M$), then it must be proven that $F$ is an homeomorphism.  Because $M$ is compact and is Hausdorff (since it's a metric space), if $F$ is continuous and bijective then it's an homeomorphism.   I have already proven the continuity and injectivity from the preservation of distances, but I'm not sure how to prove exhaustivity.


Ability to set even below the minimum brightness on iPad

In the night the lowest brightness setting on iPad (1st gen) is still too bright.  Is it possible to set it even lower somehow?  On iBooks it's possible but it works only on iBooks itself and not on whole iPad.  running the latest iOS 5.1


Is the distance between the Sun and the Earth increasing?

$M$ = mass of the Sun  $m$ = mass of the Earth  $r$ = distance between the Earth and the Sun  The sun is converting mass into energy by nuclear fusion.   $$F = \frac{GMm}{r^2} = \frac{mv^2}{r} \rightarrow r = \frac{GM}{v^2}$$  $$\Delta E = \Delta M c^2 = (M_{t} - M_{t+\Delta t}) c^2 \rightarrow \Delta M = \Delta E / c^2$$  $$\rightarrow \frac{\Delta r}{\Delta t} = \frac{G}{v^2 c^2}.\frac{\Delta E}{\Delta t}$$  Sun radiates $3.9 × 10^{26}~\mathrm W = \Delta E/\Delta t$  Velocity of the earth $v = 29.8 \mathrm{km/s}$  There is nothing that is stopping the earth from moving with the same velocity so for centripetal force to balance gravitational force $r$ must change.   Is $r$ increasing? ($\Delta r/ \Delta t = 3.26070717 × 10^{-10} \mathrm{m/s} $)


Getting first element of ArrayList takes longer than getting other elements

I want to measure time of getting elements of ArrayList. I know that using ArrayList we can get any element in constant time. I tried to check this writing code, but it returns wrong result for first element.  My code:  private long getGetTime(int position) {     long elapsedTime = 0;     long start = System.nanoTime();       list.get(position);      long end = System.nanoTime();     elapsedTime = end - start;      return elapsedTime; } preapareStructure(); System.out.println("read 0, time: " + getGetTime(0)); System.out.println("read size/2, time: " + getGetTime(list.size()/2)); System.out.println("read size-1, time: " + getGetTime(list.size()-1));   And this returns something like this:   read 0, time: 10243 read size/2, time: 843 read size-1, time: 843


I found an old DVD disc that i burned some stuff on almost 10 years ago. I have no use for that stuff anymore but i need the DVD disk to save some data. I tried deleting it the old fashiond way, and reformatting the disk with the Disk Utility app but no luck it always says that the content on the disk are read only files.


I'm trying to get a table of content in my slides. I've found a minimal example here on the site:  \documentclass{beamer} \usepackage[english,ngerman]{babel}  \begin{document} \begin{frame} \tableofcontents \end{frame}  \section{Section 1} \begin{frame} \frametitle{slide1} slide 1 \end{frame}  \end{document}   I am using Mac and the terminal command pdflatex. If I do this the result is a pdf with two slides, but the first one stays empty.


I'd like to remove the title bars in Gnome Shell. Running Ubuntu 18.04 with Gnome and the Adwaita theme.   Is there a file I can edit to remove the title bars off the windows? It's really wasted space. I use shortcut keys to close windows, press alt if I need menus, and move things around with alt + mouse click. I'd love to give that screen real estate back to my browser or terminal.   Extensions don't seem to work. I want to know where in the code of the theme these title bars are so I can either delete them or change them. I remember doing this in the past, but don't want to hack away at files indiscriminately like last time.


How to trace out qubits from a multipartite density matrix

I have a density made up of 4 qubits. Say system A is made up of the first and second qubits while system B is made up of qubits 3 and 4. I want to trace out 2nd and 3rd qubits. Is there any reference available to trace out qubits from a multipartite density matrix?


Is there any official etiquette for placing images in blockquotes? I usually just put them in the post without blockquotes. Also, sometimes edits are just made to add blockquotes to images. This image is out of blockquotes:    This image is inside of the blockquotes:        Which is preferred?


How to find a text file which contains a specific word inside (not in its name)

I want to find a text file in my hard disk which contains a specific word.  Prior to Ubuntu 12.4 I used to start in the dash an application, I think it was called "Search for file...", whose icon was a magnifying glass.I can't find that simple application any more.


Rey stole his ship, and he was talking to Han. There didn't seem to be any other ships there.


I own Fuji X100T; it's 35mm equivalent. Now I am looking at wide angle WCL-X100 conversion lenses, it is 0.8x.  is one review, just to know what I am talking about.  What is the purpose of this 0.8x wide angle? I mean, you get wider image, but isn't that the same if I just go some steps back?  Where I would use it? I guess it pays of for shots in nature, when subject is far away? Or? Where I would use it?


I am a new learner of Stripe. How to Integrate Stripe to salesforce using REST API? and How it works? Could you please give me any ideas..


When I build my server image, I write the following to a temporary file;  * * * * * php /var/www/artisan schedule:run   and then load it with  crontab < /tmp/cron   After deployment of the image, I run cron -f and I can see that the process is indeed running, but the cronjob is not being initiated.  If I run crontab -e, add a space, save it, run crontab -e again and remove the space, the cronjob working just fine without reload of cron.  I've tried reloading the cron on build with /etc/init.d/cron reload, but this does not solve the issue.


White light is a mixture of different wavelengths.   If so what will be the structure of a beam of white light ? Is there a separation between different colours ? what does it actually mean ?  Does a beam of white light shows any spacing between different wavelengths ?


Z-axis issue with the floating review info panel, permits various elements to flow over it

I was having a look at an old question of mine when I browsed the  from the timeline. I scrolled downwards and realized the Review completed panel comes along for the ride. While that might be , tags flowing over top of it as pictured below probably isn't.  Here's a .gif of the Question and Duplicate tabs flowing over it as well. Note that the timeline button also flows over. If vote buttons are present, they will also flow over it.  Reproduced on Chrome and Microsoft Edge. Update Per  by Tiago Martins Peres, this issue also happens in other Review types, namely Late Answers, First Posts and Low Quality Posts. In addition to that, it is causing the action buttons on reviews to become unclickable if you scroll low enough.  As a temporary workaround, you can use 's , which  this issue.


What does regular expression (?<=[\\S])[\\S]*\\s* do?

I saw a regex expression in  other stackoverflow question but I didn't understand the meaning of each part.  String[] split = s.split("(?<=[\\S])[\\S]*\\s*");   The result of this is the Acronym of a sentence.  In order to understand a chaining regex expression should I start reading it from left to right or viceversa? How can I identify (or limit) each part?  Thank you for your answers.


How can you use vector blur in Cycles with fluids?

I know (at least I believe this to be true) that using cycles motion blur wont work with fluid simulations when rendering, however, I know that vector blurs can be used in place of motion blur.  With that said, however, I seem to be unable to get the vector blur to work in a cycles render of fluid. I have generate vectors enabled as well.  This doesn't seem to make sense to me, since vector blurs are applied after the render in compositing and therefore, in my opinion, shouldn't be affected by the rendering engine.  Any thoughts? Help?


Trying to deploy Automatic Attachment Cloning trigger between two custom objects

I try to deploy a trigger from sandbox tp production but my test class does not fill the code coverage of the trigger it is supposed to check.  I am new to Apex (or Java) & don't know what is missing.  Trigger  trigger Copy_Attachments_from_Invoice on DATEV1__AccountingDocument__c (after insert) { {     Attachment[] attList = [SELECT id, name, body from Attachment where parentid = :Trigger.new[0].Supplier_Invoice__c];      Attachment[] insertAttList = new Attachment[]{};      for(Attachment a : attList)      {         Attachment attach = new Attachment(name = a.name, body = a.body, parentId = Trigger.new[0].Id);          insertAttList.add(attach);     }      if(insertAttList.size() > 0)      {         insert insertAttList;     }  } }   (this already works in sandbox, yay!)  Test class  @isTest  public class Test_Copy_Attachments_from_Invoice {      static testMethod void testCopy_Attachments_from_Invoice () {           Supplier_Invoice__c si = new Supplier_Invoice__c();          insert si;                 Attachment attList = [SELECT id, name, body from Attachment where parentid = :si.id];          attList.Name       = 'Unit Test Attachment 1';          attList.body       = Blob.valueOf('Unit Test Attachment Body 1');          attList.parentId   = si.id;            insert attList;               // -- Retrieve saved & generated attachments             List <Attachment> attachments = [select id, name, body from Attachment where parentid=:si.id];         List <Attachment> attachments2 = [select id, name, body from Attachment where Name = 'Unit Test Attachment 1'];      }    }   At least it doesn't show me any errors anymore after doing a lot of trial & error but when I run it it doesn't fill the code coverage.  Thanks for your help!!!!


How do I set up an account with multiple users?

Our organisation wants to set up a single Twitter account identity with multiple users from the organisation. How do we do that?


I'm really interested in getting into serious or even professional photography. I've read some articles about fundamental concepts like aperture, exposure, ISO sensitivity, etc., and I want to get the feeling of how changing different setting affects the resulting picture.  My point-and-shot camera has a manual mode but it seems like no matter what kind of settings I select, I always get worse results than if I shoot in auto mode.  Some people claim that manual mode on point-and-shoots is a joke. Should I get a "real camera"?