How can I create chapter "Title Pages"?
Fancy chapter headings
The "I Get It" Reputation Problem Key Derivation Functions vs. Password Hashing Schemes Key derivation functions, such as HKDF (standardized in ), are meant to stretch some initial keying material having enough entropy, like a Diffie-Hellman shared value, into one or more strong cryptographic secret keys.   Password-hashing schemes, such as the  winner , are meant to hash usually low-entropy passwords with the goal of making the hash digest inversion as costly as possible for an adversary with respect to CPU and memory consumption, as well as parallelization.  Is it exact to consider that password-hashing schemes are actually key derivation functions specialized for low-entropy inputs? Or is there any other essential difference of theoretical nature between these two types of cryptographic schemes? Notepad++ incrementally replace What's the difference between passing by reference vs. passing by value? How does virtualizing differ from emulation, in terms of structure? Someone told me that a virtualizing program like VirtualBox does not work like an emulator does in the sense that it doesn't emulate registers and uses the actual ones for the virtualized data that are on the CPU. Emulators must emulate the registers since they are mostly to execute software that depends on a foreign environment (e.g. a Genesis emulator needs Motorola 68000's registers and memory addresses, so developer must make these resources available as emulated registers).  My main question is, how is virtualization developed? How do we enable an entire OS to run as a process in a virtual machine, but get it to run independently while still making use of the actual CPU? I only know emulation, not virtualization, so if anyone could help that'd be nice!  PS: I am not asking solely what the difference is, but differences in how they run software. How do I pass a function as a parameter to in elisp? I'm trying to pass one method to another in elisp, and then have that method execute it.  Here is an example:  (defun t1 ()   "t1")  (defun t2 ()   "t1")  (defun call-t (t)   ; how do I execute "t"?   (t))  ; How do I pass in method reference? (call-t 't1) Prove that the functions $f(z)$ and $\overline{f(\overline{z})}$ are simultaneously holomorphic.   I take this to mean that $f(z)$ is holomorphic if and only if $\overline{f(\overline{z})}$ is holomorphic.  Let $g(z)=\overline{f(\overline{z})}$. Note that $\overline{g(\overline{z})}=f(z)$. So it suffices to prove that if $f(z)$ is holomorphic, then $g(z)$ is holomorphic.  Write $f(z)=u(z)+iv(z)$. Since $f(z)$ is holomorphic, the real and imaginary parts satisfy the Cauchy-Riemann equations:  $$\frac{\partial{u(z)}}{\partial{x}} = \frac{\partial{v(z)}}{\partial{y}}, \frac{\partial{u(z)}}{\partial{y}} = -\frac{\partial{v(z)}}{\partial{x}}.$$  We have $g(z) = u(\overline{z})+i(-v(\overline{z}))$. To prove that $g(z)$ is holomorphic, we must prove that its real and imaginary parts satisfy the Cauchy-Riemann equations:  $$\frac{\partial{u(\overline{z})}}{\partial{x}} = \frac{\partial{(-v(\overline{z}))}}{\partial{y}}, \frac{\partial{u(\overline{z})}}{\partial{y}} = -\frac{\partial{(-v(\overline{z}))}}{\partial{x}}.$$  How can we obtain this from the above relations? RMSE vs Standard deviation in population Imagine you are surviving in the wilderness traveling in a wandering manner. You've found this landscape that is wonderfully abundant in food and basking in a very favorable climate. Therefore, you decide that this is your new residence.  Night is approaching, so you haphazardly piece together a makeshift shelter to make for a more enjoyable living experience while you get your act together.  This shelter is only temporary. After you've become familiar with the land and have gathered finer resources, you will begin creating a proper home complete with securities, amenities, and furnishings.  The word I am looking for is an adjective meaning something similar to "created recklessly for temporary use."      The shelter you were building on your first night was a(n) ________   abode.   The words and phrases "ad-hoc", "off the cuff", "on the run" came to my mind, but none of those are understood to mean what I am trying to communicate (in fact, two of them are not even close). If you think of a word with a meaning that you believe to be similar to what I am searching for, I'd love to hear from you!  Thank you. Remove files with 0 length inside bash I want to create a bash script inside Linux terminal to go into a file and then delete it if it's empty:  #!/bin/bash echo " Enter name of a directory" read Dir for Directory in $( ls $HOME ) do    test -d $HOME/$dir   if [ $# -eq 0 ]   then      for filename in $( ls $HOME/$Dir )     do        test -d $HOME/$dir/$filename       if [ ! -s "$filename"  ]       then         rm $HOME/$dir/$filename       else          echo " not empty"       fi      done    else      echo " $Dir is not a directory"    fi  done   This is the code I am using but it does not work. It recognizes the file created but doesn't delete it even when empty. It Salah displays there is no such file or directory ^x^y unix trick for all instances in last command? One of my favorite Unix tricks is ^x^y, which will take the last command and replace the first instance of "x" with "y". However, I'm wondering if a similar trick works to replace all instances of "x" with "y" in the last command? How do I arrange selected vertices into a circular formation quickly?  The other answers does not have the same title as my question. My question is direct and simple for younger beginner to search for results. When does function composition commute? I've read that function composition "generally does not commute."  Not counting compositions involving the identity function, and compositions of a function and its inverse, are there examples of functions on the reals (for example) $f, g$ where $fg = gf$ outside of these cases? I compile my project with VIsual Studio 2005 Express Edition, and get this linking error. Can anyone suggest how to solve that? Is it correct to say "I wrote him" or "I wrote to him"?  My Mother was a stickler for English grammar and would say "I wrote your Uncle..." rather than "I wrote to your Uncle..." Does Java have buffer overflows? Prove that for any piecewise smooth curve it is possible to find the parametrisation I have started a long process through a terminal. Is it possible to make the Ubuntu terminal make a sound once the process is complete? This way, I don’t need to keep checking, but will instead be notified through a sound. I am trying to show that: \begin{equation} \frac{n}{\phi(n)} = \sum_{d \mid n} \frac{\mu^2(d)}{\phi(d)} \end{equation} where $\phi(n)$ is  and $\mu$ is the .  The identity clearly holds for $n=1$, so if we write $n=p_1^{a_1} \cdots p_k^{a_k}$ for the prime decomposition of $n$, the left-hand side becomes: \begin{eqnarray*} \frac{n}{\phi(n)} &amp; = &amp; \frac{p_1^{a_1} \cdots p_k^{a_k}}{\phi(p_1^{a_1}) \cdots \phi(p_k^{a_k})} \\ &amp; = &amp; \frac{p_1^{a_1} \cdots p_k^{a_k}}{(p_1^{a_1-1})(p_1-1) \cdots (p_k^{a_k})(p_k-1)} \\ &amp; = &amp; \frac{p_1 \cdots p_k}{(p_1-1)\cdots (p_k-1)} \end{eqnarray*}   Whereas the right-hand side becomes:  \begin{eqnarray*} \sum_{d \mid n} \frac{\mu^2(d)}{\phi(d)} &amp; = &amp; \sum_{\substack{d \mid n \\ p^2 \nmid d}} \frac{1}{\phi(d)} \\ &amp; = &amp; 1 + \frac{1}{\phi(p_1)} + \dots + \frac{1}{\phi(p_k)} + \frac{1}{\phi(p_1 p_2)} + \dots + \frac{1}{\phi(p_{k-1}p_k)} \\ &amp; + &amp; \dots + \frac{1}{\phi(p_1 \cdots p_k)} \\ &amp; = &amp; 1 + \frac{1}{p_1 - 1} + \dots + \frac{1}{p_k - 1} + \frac{1}{(p_1 - 1)(p_2 - 1)} + \dots + \frac{1}{(p_{k-1}-1)(p_k-1)} \\ &amp; + &amp; \dots + \frac{1}{(p_1 - 1) \cdots (p_k - 1)} \end{eqnarray*}  I am unsure of how to proceed from this point however. Any help would be much appreciated. How to create a batch job, numbering images (writing text on them) from 1 to 100 in Photoshop? Looking to create a 100 images that would have their appropriate numbers written on them.  Since I`ll be most likely making changes to the template in the future I figured it would be better to automate it somehow.  Is there a simple solution to this problem?