For university, i like to print out my professors scripts. They usually use beamer- or powerpoint presentations throughout the lectures.  My goal is to have two presentation sheets on one A4 page.  With Adobe Acrobat, this seems to be not so big of a deal but since i switched to Linux completely, i would like to find a solution that works fine without having to use acroread, pdfstudio or another closed source program.  I tried printing with evince, okular and several other applications (which all feature multi-page-printing-options), but the results were often not rotated incorrectly or where scaled much too small. Not having a print-preview doesn't make things easier.  So my newest idea would be to create a new .pdf with imagemagick and have two sheets on one page, one above the other so that i can print it out as big as possible.  Imagemagick should be capable of doing that, but i don't know the right commands!  If there's anyone knowing other/better solutions to the problem, you're of course welcome to share!
I have a PDF with 100 pages. How can I make a new PDF that displays 4 pages on one?  I know that I can do it with Chrome by printing the PDF to new PDF and change this in the options. But I want to make it for a lot of files and put it as a script.
What would be the quickest way to construct a Python binding to a C or C++ library?  (I am using Windows if this matters.) How do I remap certain keys or devices? Can noindex tags on several pages affect the overall SEO or ranking on Google? Some SEO Gurus assured me that noindex attributes are good to devalue the unimportant pages.   When I asked in the moz Q and A, they're quite sure that having noindex on the bulk of the articles on the website can harm overall SEO ranking.   Which is true? I've found ,  and  which are releated to my question, but no longer seem to apply since Drupal 8.1 and the deprecation of .  Also popular guides such as  appear to no longer apply as they also mention composer manager.   The other solution opposed to composer manager, alter the core composer.json file feels like too much core hacking and would probably break with every Drush update of Drupal core(?).  More specifically, I am attempting to update  from Drupal 7 to 8. I have created my composer.json file as follows:  {   "name": "drupal/views_vcards",   "description": "Allows creation of vCards using the fields provided by the Views module.",   "type": "drupal-module",   "license": "GPL-2.0+",   "homepage": "https://drupal.org/project/views_vcards",   "require": {     "maennchen/zipstream-php": "0.3.*"   } }   But if I put a composer.json file in my module folder, how do I make Drupal aware that that file is there, and how do I make sure the required zipstream-php library is downloaded?  Simply running composer update from the Drupal root does update a lot of Drupal dependencies, but it does not include the composer.json files that are in the modules folders. I also don't assume I should be calling composer install from inside all modules with dependencies.  How do I make Drupal aware of a module's dependency without using composer manager and/or hacking core?  UPDATE:  The  appears to have support a wildcard path:  {     "require": {         "wikimedia/composer-merge-plugin": "dev-master"     },     "extra": {         "merge-plugin": {             "include": [                 "composer.local.json",                 "extensions/*/composer.json" // &lt; ---- THIS LINE             ],             "require": [                 "submodule/composer.json"             ],             "recurse": true,             "replace": false,             "merge-dev": true,             "merge-extra": false         }     } }   Why doesn't core merge modules/*/composer.json, that would solve everything right?  Update 2:  THe reasoning for not supporting this is covered in  (which also has been quiet for some time now). How to wait for a shell process to finish before executing further code in VB6 Example sentence:     I love when your dog just lets you sit there to pet them. You don’t necessarily know if they are enjoying it, but they love you enough to just sit there with you for a bit.   Is this correct? We assume the words "you" and "your" refer to the speaker of the sentence, and not to the listener, as second-person usually does. But it also refers to dog owners in general. I have always been curious about this. Unexpected voltage with switch turned off I am doing some work on a ceiling light and I notice that, even though the light-switch is off, my voltage tester shows voltage present.  Answers to other questions (below) explain about phantom voltages but how exactly do I test for these and know what voltages are real and what are phantom so that I can work safely?    Phantom voltage questions I just upgraded my texlive distribution and can no longer insert space in table rows using \\[x pt] syntax when colortbl is loaded.  It seems that recent changes to array.sty might be the problem as this is the only package to change recently.  Can anyone suggest a workaround?  MWE  \listfiles \documentclass{article} \usepackage{colortbl} \begin{document} \begin{tabular}{l}   \hline   No space below with \texttt{colortbl.sty} loaded. \\[10mm]   \hline \end{tabular} \end{document}   File versions in use:   article.cls    2014/09/29 v1.4h Standard LaTeX document class   size10.clo    2014/09/29 v1.4h Standard LaTeX file (size option) colortbl.sty    2012/02/13 v1.0a Color table columns (DPC)    array.sty    2018/04/07 v2.4g Tabular extension package (FMi)    color.sty    2016/07/10 v1.1e Standard LaTeX Color (DPC)    color.cfg    2016/01/02 v1.6 sample color configuration   pdftex.def    2018/01/08 v1.0l Graphics/color driver for pdftex Separate Models vs Flags in the same model I have customer data from 2 brands. The data structure are the same, but I expected the customer behaviour to be different in different brand.  So I could train 2 models, 1 for each brand, or I could train one model on both brands, but flag which brand the customers belongs to within the data.  So my question is, would training on both brands with flags be too much more work for the Machine Learning (I'm using neural network), and therefore be harder to achieve good accuracy than to have dedicated models for each brand? Applying for a Canadian ETA after previous visits without one My proof is very different from my reference, hence I am wondering is I got this right?  Apparently, $F$ is continuous, and the identity matrix is closed. Now we want to show that the preimage of continuous function on closed set is closed.  Let $D$ be a closed set, Consider a sequence $x_n \to x_0$ in which $x_n \in f^{-1}(D)$, and we will show that $x_0 \in f^{-1}(D)$.  Since $f$ is continuous, we have a convergent sequence $$\lim_{n\to \infty} f(x_n) = f(x_0) = y.$$  But we know $y$ is in the range, hence, $x_0$ is in the domain. So the preimage is also closed since it contains all the limit points.  Thank you. How to print a date in a regular format? How to avoid pressing Enter with getchar() for reading a single character only? How to link a variable of a material to another material? I've used recursion quite a lot on my many years of programming to solve simple problems, but I'm fully aware that sometimes you need iteration due to memory/speed problems.  So, sometime in the very far past I went to try and find if there existed any "pattern" or text-book way of transforming a common recursion approach to iteration and found nothing. Or at least nothing that I can remember it would help.   Are there general rules? Is there a "pattern"? Can there be two winners at the same time in Catan? Imagine the following setup:    Player A has 6 points, including the Longest Road. Player B has 8 points with an equally long road. Player C has 9 points with a shorter road.    Now what would happen if Player C places a village, breaking Player A's road chain? At that moment Player A would have 4 points, while both Player B and Player C would have 10.   In this case, who would be declared the victor? $|p(z)| \leq M$ for $|z| \leq 1$ Show that $|p(z)| \leq M|z|^n$ for $|z| \geq 1$ Let $p(z)= \sum_{k=0}^n a_k z^k$ ,  $a_n \neq 0$ , be a polynomial of degree $n$ such that $|p(z)| \leq M$ for $|z| \leq 1$.  Show that $|p(z)| \leq M|z|^n$ for $|z| \geq 1$  This was an exam question. Part (a) of this question asked the converse: if $|p(z)| \leq M|z|^n$ and $|z|$ is sufficiently large, then $p(z)$ is a polynomial. This question came straight out of Ahlfors' Complex Analysis, which I solved by showing, using the Cauchy Estimate,  $|p^n (z)|  \leq \frac{n!M|z|^k}{R^n} = 0$ as $R \to \infty$.   I would like to work backwards with this.   May I do this, or similar:   $p(z) = \frac{1}{2\pi i} \int_{c} \frac{f(\zeta)d\zeta}{\zeta-z}$  $\Rightarrow  |p(z)| \leq \frac{2\pi M|z|^n}{1(2\pi)}= M|z|^n$ Were I rich, I would live on Long Island.   If I were rich, I would live on Long Island.   Is the first sentence still used, or is used in particular contexts (in example, to give emphasis to the sentence)? Proving that $\sum\limits_{k=0}^{n} {{m+k} \choose{m}} = { m+n+1 \choose m+1 }$ I have to prove that:     $$\sum_{k=0}^{n} {{m+k} \choose{m}} = { m+n+1 \choose m+1 }$$   I tried to open up the right side with Pascal's definition that: $$ { n \choose k} = {n-1 \choose {k}} + {n-1 \choose {k-1}}$$  Here is what I came up with, and I am sure it is wrong because it does not equal the left side:  $$ {m+n+1 \choose m+1} = {m+n \choose m+1} + {m+n \choose m} = ... ={m+n \choose m+1} + {m+n-1 \choose m} + {m+n-2 \choose m-1} + ... + {m \choose m+1} = \sum_{k=0}^{n} {m+k \choose m+k-n+1 }  $$  Which, again, probably is wrong because it is not equal $\sum_{k=0}^{n} { m+k \choose m}$. Any help is appreciated What are the fundamental differences between the mainstream *NIX shells? What are the fundamental differences between the mainstream *NIX shells and what scenarios might prompt you to use one over the other?  I understand that some of it probably comes down to user preference but I've only ever used Bash and I'm interested to hear where another shell might be useful. Also, is there an impact on user-written shell scripts when running under one shell or another or is it simply a matter of changing the shell at the top of the file?  My instinct says it's not that easy.