Do Windows memory optimizers actually work (on Windows 10)?
Memory and CPU optimizers: Are they gimmicks?
What are XML namespaces for? This is something that I always find a bit hard to explain to others:  Why do XML namespaces exist?  When should we use them and when should we not? What are the common pitfalls when working with namespaces in XML?   Also, how do they relate to XML schemas? Should XSD schemas always be associated with a namespace? Calculating the optimal number of bins for severely skewed data Send file using POST from a Python script Extracting embedded images from a PDF Best way to detect when a user leaves a web page? What is the best way to detect if a user leaves a web page?  The onunload JavaScript event doesn't work every time (the HTTP request takes longer than the time required to terminate the browser).  Creating one will probably be blocked by current browsers. $\mathcal N (A):=\mathcal P(A)\setminus\{\varnothing\}$ notation Move EFI System Partition to another drive I have been reading the top posts here, and the recommendations for what to invest in are often similar. What I'd like to know, in as simply of terms as possible, is what the consensus is on priority of these investments.  I am new to this, but here are some of the obvious options:   Paying off credit card debt Paying off mortgage / student loans 401k up to employer match 401k past employer match IRA Emergency fund Other important investments that I have missed   Clearly this will vary person to person, but if you were asked to put an ordered recommendation on a highway billboard, what would it be?  (For example:   Pay off credit debt Emergency fund for 6 months 401k up to match ... ) I have currently a strange problem on debian (wheezy/amd64).  I have created a chroot to install a server (i can't give any more detail about it, sorry). Let's call its path /chr_path/. To make things easy, I have initialized this chroot with a debootstrap (also wheezy/amd64).  All seemed to work well inside the chroot but when I started the installer script of my server I got : zsh: Not found /some_path/perl (the installer includes a perl binary for some reasons)  Naturally, I checked the /some_path/ location and I found the "perl" binary. file in chroot environment returns :  /some_path/perl ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.2.5, not stripped   The file exists, seems ok, has correct rights. I can use file, ls, vim on it but as soon as I try to execute it - ./perl for example - I get : zsh: Not found ./perl.  This situation is quite understandable for me. Moreover :   I can execute other basic binaries (/bin/ls,...) in the chroot without getting errors I have the same problems for other binaries that came with the project When I try to execute the binary from the main root (/chr_path/some_path/perl), it works. I have tried to put one of the binaries with a copy of my ls. I checked that the access rights were the same but this didn't change anything (one was working, and the other wasn't) I just failed these   in First Post, I read the question and thought it seemed reasonable but the user was deleted so to be on the safe side I clicked add comment and I failed the audit.  I'm not sure why adding a comment would be considered a negative action, is the correct option to click No Action Needed or edit?  What was I supposed to do in this situation?  Adding a comment should not be a review audit fail. Prove $a^\alpha b^{1-\alpha} \le \alpha a + (1 - \alpha)b, \; a,b > 0,\; 0 < \alpha < 1$ I have no idea how to do this. Any help would be appreciated. The chapter I'm on is about differentiation and the mean value theorem.  Prove $a^\alpha b^{1-\alpha} \le \alpha a + (1 - \alpha)b, \; a,b &gt; 0,\; 0 &lt; \alpha &lt; 1$ Why isn't persistence working on Lubuntu 12.04 Live-USB? Calculation of the avalanche effect coefficient Given a  matrix/dependence matrix for a hash function,how do I calculate the avalanche coefficient for it. I want to calculate a single parameter(value) which represents the amount of avalanche effect for the given hash function.  I have thought of computing mean all over the matrix but am not sure that's the correct thing to do.  The  talks about the avalanche coefficient but they haven't mentioned the way they calculate it. I have had a question since childhood.  Why do we always get circular waves (ripples) in water even when we throw irregularly shaped object in it? Differences between hash- and encryption algorithms? There is a lot of confusion between hash- and encryption algorithms; I would like to understand:   When do we use a hash algorithm and when do we use an encryption algorithm (a cipher)? How difficult it is to reverse hash- and encryption algorithms? From the theoretical/mathematical perspective, what differentiates a hash- and encryption algorithm? I am travelling to Budapest and therefore have a Schengen Visa. I hold an Indian passport and a valid US visa. I'm travelling from Chicago-Heathrow-Budapest and returning by Budapest-Dublin-Chicago.  Would I need a transit visa for UK/Ireland?  UPDATE  Hoping this will help someone someday.   I was not allowed to board my return flight (BUD-DUB-ORD) because I do not hold an overnight Irish Transit Visa. They said I could have transited happily if the connecting flight was in the same day, but because I would have to originally land at 10 PM and catch the connecting flight next morning at 10 AM, I needed a transit visa. Well, I thought it was BS, but couldn't help comply with the rules. I booked another last minute ticket and flew via Warsaw via LOT. How can I buy apps in the App Store without a credit card? Under TeX, when I write a line too long, it prints a fat black box at the end of the line.  That is probably a feature, but I dislike it.  How to turn that OFF? Is there a command-line option or something else?   I usually use LaTeX, but I have a complicated file which happens to be plain TeX. Let $Z_n$ be the set of all $n \times n$ matrices that commute with all $n \times n $ matrices. Show that $$Z_n = \{\lambda I_n \ | \  \lambda \in \mathbb R\}$$  ($I_n$ is the $n \times n$ identity matrix)  I don't know how to use $E_{ij}$ (matrix with $1$ in $(i,j)$ and $0$ elsewhere) and the elementary matrix $P_{ij}$ to prove this question. Can anyone explain it please? Are there infinitely-many numbers that are both square and triangular? I just started to read "Friendly Introduction to Number Theory" but I am getting stuck in the first exercises.     1.1. The first two numbers that are both squares and triangles are 1 and 36. Find the next one and, if possible, the one after that. Can   you figure out an efficient way to find triangular–square numbers? Do   you think that there are infinitely many?     I found how to find out the number which is both square and triangle. (don't know if this is effective way)    However how can I answer "Do you think that there are infinitely many?"? I think I need to find the formula but no idea yet. Can you please help me?