transparent PNG image not working in cycles
How can I setup a Material in Cycles for Z-Transparency?
underbrace matrix inside brackets I would like to put an underbrace below the matrix like this:  $$\left(\underbrace{ \left[\begin{array}{ccc}     a&amp;b&amp;c\\     d&amp;e&amp;f\\     g&amp;h&amp;i \end{array}\right]}_{A} \left[\begin{array}{c}     x_1\\     x_2\\     x_3 \end{array}\right]\right)$$     But I don't want the outer brackets \left( and \right) to stretch vertically. I want them to remain as if there was no underbrace. How to achieve that behaviour? The state postulate is as follows: The state of a simple compressible system is completely specified by two independent, intensive properties. My first question is whether there is any justification for this postulate or whether it is simply an empirical law? That is, why is it not the case that 3 intensive variables are required to fix the state or even 4? If it is an empirical law with no justification and just happens to be a law our universe abides by, then why is it not one of the laws of thermodynamics as it clearly provides foundational value to the field of thermodynamics? My second question pertains to how we can know whether 2 intensive variables are in fact independant. Say temperature $T$ and specific volume $v$ for example. If we are given a thermodynamic problem, how would we know whether these are independent or not? or perhaps specific internal energy $u$ and pressure $P$. Are there certain combinations that are simply always independent of each other or does independence between intensive variables vary from problem to problem and require a full understanding of the problem at hand? Let us take a phase change for example. From my understanding of phase changes, I know that the boiling temperature is dependent on the pressure and hence I won't be able to use $T$ and $P$ as 2 variables to completely specify the state. But how would I know know what combinations of intensive variables will be independent in this case or any other case for that matter? Does it simply require rote memorization of all independent pairs of intensive variables for all thermodynamic problems or is there a more simple way to figure out what is independent and what isn't? I hope this question makes some sense and any help would be most appreciated! I know there is a method for a Python list to return the first index of something:  &gt;&gt;&gt; l = [1, 2, 3] &gt;&gt;&gt; l.index(2) 1   Is there something like that for NumPy arrays? Some people use a term for a popular special case in place of a generic term.  (Often this popular special case is a particular product in that category.)  I think that this is a common phenomenon.  Is there any word/phrase for it?  For example, “Coke” officially refers to a  (I think), but some people seem to call any carbonated soft drinks “Coke.”  In Japanese, famikon is the Japanese name for , a video game console which was extremely popular in 1980s and early 1990s, but some Japanese people call any video game console famikon even if it is not really a famikon.  (As an aside, calling a video game console famikon when it is not really a famikon is even a stereotype of a “mother unfamiliar with technology” in Japan.)  I am looking for a term which refers to this kind of usage of words. In the United States we have a saying, "your mileage may vary", which means "your experience may be different".  In English-speaking countries that don't use Imperial miles, is there an equivalent expression? 'Drop us a line' - letter or phone call? According to , dropping someone a line means sending them a short message.  Is this correct? I always thought it meant phoning someone, the line referring to a telephone line. Windows 10 thinks it's up to date, but it's not How do I craft command blocks? I went to my friends house, and he was playing Minecraft on the PC. He showed me a command block, but when I went home and opened Minecraft pocket edition, I went to the crafting table but I could not find any command blocks to craft.  What are command blocks and how do I craft them? I want to be able to ask a question by sending an email to some special email address for Stack Overflow. I have found this convenient in other situations like Google Groups, blogging, and Facebook walls, and it seems that technically it shouldn't be too hard to do.  Does this feature exist already? I'm kind of afraid to ask for features as some of them get downvoted simply since users think they are not neccessary (and not because the post is bad). I just updated my iMac to Mojave, and am still trying to setup my preferences.  I tried dark mode, but did not like it (half of me apps seem to ignore it anyway).  I switched to light mode, but this too has problems. The File Save dialog shows a list of Directories and existing files, but the latter are very light grey, almost indistinguishable from the background.    I have searched the Preferences menu, but can't seem to find any setting to set normal contrast levels like in High Sierra. How to prove that $A_5$ has no subgroup of order 30? How to make sure an application keeps running on Linux I'm trying to ensure a script remains running on a development server. It collates stats and provides a web service so it's supposed to persist, yet a few times a day, it dies off for unknown reasons. When we notice we just launch it again, but it's a pain in the rear and some users don't have permission (or the knowhow) to launch it up.  The programmer in me wants to spend a few hours getting to the bottom of the problem but the busy person in me thinks there must be an easy way to detect if an app is not running, and launch it again.  I know I could cron-script ps through grep:  ps -A | grep appname   But again, that's another hour of my life wasted on doing something that must already exist... Is there not a pre-made app that I can pass an executable (optionally with arguments) and that will keep a process running indefinitely?  In case it makes any difference, it's Ubuntu. Error after installing search service application I got this this error after setting up Search Service Application with Powershell.     The search service is not able to connect to the machine that hosts the   administration component. Verify that the administration component      'a23fd668-f823- 4ab2-b0fc-b0baebfd4af2' in search application   'SharePoint_Search_Service' is in a good state and try again.   The Sharepoint Search Service was showing error when I visited   Central Administration->Application Management->Service Applications->     Manage Service Applications  Here is the powershell script used  $App1 = "APP-Server-01" $APP2 = "APP-Server-02" $SearchAppPoolName = "SharePoint_SearchApp" $SearchAppPoolAccountName = "EXSERV\Administrator" $SearchServiceName = "SharePoint_Search_Service" $SearchServiceProxyName = "SharePoint_Search_Proxy" $DatabaseName = "SharePoint_Search_AdminDB"   Create a Search Service Application Pool  $spAppPool = New-SPServiceApplicationPool -Name $SearchAppPoolName -Account     $SearchAppPoolAccountName -Verbose   Start Search Service Instance on all Application Servers  Start-SPEnterpriseSearchServiceInstance $App1 -ErrorAction SilentlyContinue Start-SPEnterpriseSearchServiceInstance $App2 -ErrorAction SilentlyContinue Start-SPEnterpriseSearchQueryAndSiteSettingsServiceInstance $App1 -ErrorAction         SilentlyContinue Start-SPEnterpriseSearchQueryAndSiteSettingsServiceInstance $App2 -ErrorAction        SilentlyContinue   Create Search Service Application  $ServiceApplication = New-SPEnterpriseSearchServiceApplication -Partitioned -Name        $SearchServiceName -ApplicationPool $spAppPool.Name -DatabaseName $DatabaseName   Create Search Service Proxy  New-SPEnterpriseSearchServiceApplicationProxy -Partitioned -Name       $SearchServiceProxyName -SearchApplication $ServiceApplication You can use the range feature of unicode-math to set the math font for a specific unicode slots or the macro accessing the glyph. I tried this with the sum sign &amp; Latin Modern, see my example:  \documentclass{scrartcl}  \usepackage{amsmath} \usepackage{unicode-math} % use unicode in math &amp; setup math fonts \setmathfont{Asana Math} %\setmathfont[range=\sum]{Latin Modern Math} % substitute Sum sign  \begin{document}  Notice the different sum sign $\sum$, as intended.   Notice also, the difference in spacing, not intended: \begin{equation}     \begin{bmatrix}         0           &amp; \frac{1}{2}   &amp; \frac{2}{3} \\         \frac{3}{4} &amp; 0             &amp; \frac{4}{5} \\         \frac{5}{6} &amp; \frac{6}{7}   &amp; 0     \end{bmatrix}     \begin{pmatrix}         A \\         B \\         C     \end{pmatrix} \end{equation} \end{document}   However, not only the sum sign, but also the spacing in the matrices changes. With Latin Modern commented out (as in the example):  With Latin Modern active (remove % before relevant line):  Why is that? BTW, I'm using Lualatex from TeXLive 2012. Cartographic techniques for symbolizing routing data Some common problems with displaying routes created from street data, such as bus routes, include:   Routes may overlap themselves, such as when a route takes the same road in opposite directions Routes may overlap other routes that take the same street. Routes are often overly detailed, or "noisy", owing to their derivation from street data. Indicating a route's direction unambiguously without overloading it with arrows can be a challenge.   What are some techniques for dealing with these issues in order to create a practical and usable route map, such as this ? Do you know of any such public transport maps that were produced by automatic techniques rather than manual illustration/digitization?  Specifically I am using ArcGIS 10, but solutions involving other software are welcome as well.  One technique I have had some success with for dealing with 1) is using ArcMap's  with a negative offset -- assuming the lines are oriented in the direction of travel, this will offset the lines such that the right and left-hand sides are distinct and oriented as you would expect (at least for  countries, for left-hand traffic countries one would use a positive offset). However the result tends to be a bit wonky around turns, interchanges and and U-turns, and is inflexible when dealing with multiple routes.  Another possibility that I am not very familiar with but which seems promising is  -- however, I have not had much luck in finding examples of using representations for transportation maps and whether it might fit the bill. I remember coming across this fact a while ago in a pdf somewhere, but I haven't been able to find it again. Can someone show me how to prove it? I would appreciate easier proofs.  EDIT: I'm very sorry, I forgot to actually state it.  Prove that $-1$ is not a quadratic residue modulo primes of the form $4k+3$.  Thanks! 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 Why do I need an extended partition? What is an extended partition? Why do I need to use it to install Ubuntu if I already have four partitions that are factory installed? Procedure for reducing the degrees of freedom of an arbitrary system Differences in meaning when the verb tense changes (headlines)