I have multiple objects I need to boolean together, but when I apply the modifier, the UV maps get messed up in a very odd manner. It is actually visible before the modifier is applied.  Two Objects:    Before Application:    UV Map afterwards:    I can't for the life of me figure out what the problem is. I checked the face normals, made sure the meshes were manifold and applied all materials to the objects in multiple configurations.
I added textures to a minecraft character, but I realized I forgot the holes for the eyes. So I used a boolean modifier to make the holes, but it was unsuccessful. The holes appear except the texture wrap becomes messy and doesn't go around my character properly.  Without Boolean modifier   With Boolean modifier
How do I list the members of a group? How can I see all the members of a group in Linux? Let $\theta \in R^{n}$. The Fisher Information Matrix is defined as:  $$I(\theta)_{i,j} = -E\left[\frac{\partial^{2} \log(f(X|\theta))}{\partial \theta_{i} \partial \theta_{j}}\bigg|\theta\right]$$  How can I prove the Fisher Information Matrix is positive semidefinite? What rules govern forced removal from flights (due to overbooking)? I was recently surprised to see  because his flight was overbooked.  He was reportedly a doctor who needed to see patients the next morning, so he did not really want to get off, justifying the use of force.  I knew that airlines could overbook flights and deny boarding to some passengers, but I thought that kind of boarding denial would happen at the gate and that once folks had been let on, those denied boarding would be those arriving later to the gate.    Why or in what conditions is this kind of forcible removal considered OK?    Clarification following close votes from people who think this question is primarily opinion-based: By "OK" I mean the sense of "legally OK," "officially accepted," "instantiated as policy," "sanctioned by authorities," or "OK according to the regulations and policies and laws and whatever other formal rules govern forced removal from flights due to overbooking." Whether or not you personally consider it socially acceptable does not matter as an answer, unless you have formalized that into a citeable adopted form that governs what happens and want to explain the reasoning behind that rule. Can black holes actually merge? If time stops at the event horizon, can we ever detect two black holes merging? In other words, if you are a short distance away, would you encounter a spherically symmetric gravitational field, or a dipole field? I want to save a backup of my data on a remote server, but never want the backup server to see the data unencrypted. Editing a single file and backing up should not result in everything being encrypted and sent again. The remote server should preferably not even know the directory structure (and especially not the directory names).  Is there such a solution? Characterizing units in polynomial rings I am trying to prove a result, for which I have got one part, but I am not able to get the converse part.  Theorem. Let $R$ be a commutative ring with $1$. Then $f(X)=a_{0}+a_{1}X+a_{2}X^{2} + \cdots + a_{n}X^{n}$ is a unit in $R[X]$ if and only if $a_{0}$ is a unit in $R$ and $a_{1},a_{2},\dots,a_{n}$ are all nilpotent in $R$.  Proof. Suppose $f(X)=a_{0}+a_{1}X+\cdots +a_{n}X^{n}$ is such that $a_{0}$ is a unit in $R$ and $a_{1},a_{2}, \dots,a_{r}$ are all nilpotent in $R$. Since $R$ is commutative, we get that $a_{1}X,a_{2}X^{2},\cdots,a_{n}X^{n}$ are all nilpotent and hence also their sum is nilpotent. Let $z = \sum a_{i}X^{i}$ then $a_{0}^{-1}z$ is nilpotent and so $1+a_{0}^{-1}z$ is a unit. Thus $f(X)=a_{0}+z=a_{0} \cdot (1+a_{0}^{-1}z)$ is a unit since product of two units in $R[X]$ is a unit.   I have not been able to get the converse part and would like to see the proof for the converse part. How do I disable auto-maximizing of newly launched windows in GNOME? Each time I open any application, it zooms to fill-up the entire desktop and so I am always forced to use "Unmaximize" using Alt+Space menu. Shadows along edges of mesh in 3D View font-not-found error: font "HoeflerText" cannot be found -- LuaLaTex error! I am running this CV/Resume example from :   Here is a relevant fraction of the code:  \documentclass[10pt]{article} %!TEX encoding =  UTF-16 % See geometry.pdf to learn the layout options. There are lots. \usepackage[hmargin=1.25cm, vmargin=1.5cm]{geometry} %symbols - the ones you see on the left of the email and of the phone \usepackage{bbding} \usepackage{amssymb} \usepackage{eurosym} %Colors/Graphics \usepackage{color,graphicx} \usepackage[usenames,dvipsnames]{xcolor}  %Fonts and Tweaks for XeLaTeX \usepackage{fontspec,xltxtra,xunicode} \defaultfontfeatures{Mapping=tex-text} \setromanfont[Mapping=tex-text]{Hoefler Text} ...   So... when compiling with LuaLaTeX (part of MiKTeX on Windwos XP x64), I am getting the following error:  ... luaotfload | Font names database loaded: C:/Documents and Settings/Ampleforth/L ocal Settings/Application Data/MiKTeX/2.9/luatex-cache/generic/names/otfl-names .lua luaotfload | Updating the font names database: luaotfload | Scanning TEXMF and OS fonts... luaotfload | Font names database saved: %s  : C:/Documents and Settings/Ampleforth/Local Settings/Application Data/MiKTeX/2 .9/luatex-cache/generic/names/otfl-names.lua  !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !  ! fontspec error: "font-not-found" !  ! The font "HoeflerText" cannot be found. !  ! See the fontspec documentation for further information. ! For immediate help type H &lt;return&gt;. !...............................................    l.28 \setromanfont[Mapping=tex-text]{Hoefler Text}   What is wrong? How can I install this font so LuaLaTeX is picking it up? Where to download? Any other thoughts about this? I read a story once about a man who escapes from his pursuers by doing an uncontrolled jump into hyperspace. If I'm not mixing my stories up he was blind but could see through the eyes of other sighted people/animals nearby. He was able to see through his pet but it dies and he thinks he's finished - he's blind and lost in hyperspace but there's a rat on board which he eventually catches by turning off gravity and then he can see through the rat's eyes. He works out how hyperspace operates and can hop back to where he came from.   Can anyone remember the name of the story and the author? I enjoyed it when I was a kid and would like to read it again. Microsoft Edge missing in Start menu and pins Skype app in my Ubuntu system work perfectly. But today when I run the app, I see this:    How Can I fix this? Question on the stability of the solar system One of the pertinent questions about many body systems that causes me much wonder is why the solar system is so stable for billions of years. I came across the idea of "resonance" and albeit an useful concept, it hardly explains the long stability of the solar system. Normally an N body problem with inverse square mutual interaction is an example of a chaotic system. Is there any real progress about this stability issue? 16.04 new installation gives grub-efi-amd64-signed failed installation /target/ ubuntu 16.04 at the end I am installing Ubuntu 16.04 in an Intel NUC computer with UEFI enabled. I am using an SSD from another computer. During the installation I chose Erase the disk and make a new full install  At the end of the process I see:  grub-efi-amd64-signed failed installation /target/ Ubuntu 16.04    And the system does not boot.  I tried to use boot-repair but apparently it does not solve the problem. Why use "need not" instead of "do not need to"? A financial planner treated us in a dismissive fashion and I want to say that he "gave us the back of his hand" but that phrase doesn't seem to have the meaning of dismissive. Does it or is there a similar idiom? Cannot connect to internet after using airmon-ng check kill In new version of Kali 2.0 with updated "aircrack-ng" tool, there is a problem between Internet connection and using cracking tools.   I have my wireless card as wlan0. And the Internet connection is fine too. Then, what I do is:  airmon-ng start wlan0 airodump-ng wlan0mon   Now the airodump-ng doesn't work, saying "Device or resource busy".  In order to run this I have to kill some processes, using:  airmon-ng stop wlan0 airmon-ng check kill airmon-ng start wlan0 airodump-ng wlan0mon   Now the cracking process is up.   I can start cracking, but now I cannot connect to the Internet after the kill process.  On typing iwconfig in terminal, I get this:  root@kali:~#iwconfig wlan0mon IEEE 802.11bgn  ESSID:"myessid"         Mode:Managed  Frequency:2.412 GHz  Access Point: 00:00:00:00:00:00          Bit Rate=108 Mb/s   Tx-Power=20 dBm          Retry short limit:7   RTS thr:off   Fragment thr:off       Encryption key:off       Power Management:off       Link Quality=42/70  Signal level=-68 dBm         Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0       Tx excessive retries:2  Invalid misc:9   Missed beacon:0  eth0      no wireless extensions. lo        no wireless extensions.   And, on running ifconfig on terminal, I get this:  root@kali:~#ifconfig lo        Link encap:Local Loopback         inet addr:127.0.0.1  Mask:255.0.0.0       inet6 addr: ::1/128 Scope:Host       UP LOOPBACK RUNNING  MTU:65536  Metric:1       RX packets:5604 errors:0 dropped:0 overruns:0 frame:0       TX packets:5604 errors:0 dropped:0 overruns:0 carrier:0       collisions:0 txqueuelen:0        RX bytes:452904 (442.2 KiB)  TX bytes:452904 (442.2 KiB)   There is no wlan0 or wlan0mon. I also restarted the network manager by:      service network-manager restart   But nothing changed. Though it displays wlan0 when checked using ifconfig this time. So the vending machine tore my $5 in pieces. What now? The vending machine swallowed half of my $5 bill, and the other half remained in my hand. Can I get my $5 back, or is it all lost forever? how to stop firing oncomplete if save action has errors My requirement is to stop oncomplete call if save action has errors. I know I am doing some silly mistake.   Here I am unable to stop calling oncomplete function.  Requirement is, from VFP save method, data will get saved and then perform callout from oncomplete function. If there are any errors during save then stop making callouts.  Visualforce  &lt;apex:page id="hasErrorTestPage" controller="ErrorMessageFinder"  showHeader="false"&gt;     &lt;apex:pageMessages id="msgId"/&gt;     &lt;script&gt;         function performCallOutMethod()         {             var msg = document.getElementById('{!$Component.MSEForm.errorMsgInd}').value;             alert(msg);              if(msg == 'false' || typeof(msg) == 'undefined')             {                 alert('entering callout')                 performCallOut();                 return true;             }             else             {                 return false;             }         }     &lt;/script&gt;     &lt;apex:form id="MSEForm"&gt;         &lt;apex:actionFunction name="performCallOut" action="{!submit}" reRender="panelId,msgId"/&gt;          &lt;apex:outputPanel id="panelId"&gt;             &lt;apex:outputText value="{!hasError}" id="errorMsgInd"/&gt;         &lt;/apex:outputPanel&gt;         &lt;apex:inputText id="customerNm" value="{!CustomerName}"/&gt;&lt;br/&gt;         &lt;apex:commandButton value="Save" action="{!save}"                       oncomplete="return performCallOutMethod();" reRender="panelId,msgId"/&gt;     &lt;/apex:form&gt; &lt;/apex:page&gt;   Controller  public class ErrorMessageFinder {     public String CustomerName {get;set;}      public Boolean hasError {          get {              return ApexPages.hasMessages();          }            }      public PageReference save()     {            if(String.isBlank(CustomerName))         {             ApexPages.Message msg = new ApexPages.Message(ApexPages.Severity.Error, 'Name cannot be null');             ApexPages.addMessage(msg);             return null;         }         return null;      }       public PageReference submit()     {         try         {   //navigate to view page             PageReference pg = new PageReference('/'+ '0019000001UwnVS');             pg.setRedirect(true);             return pg;         }         catch (Exception ex)         {             System.debug('Error in submit ' + ex);             ApexPages.Message msg = new ApexPages.Message(ApexPages.Severity.Error, ex.getMessage());             ApexPages.addMessage(msg);              return null;         }     } }   Based on this code, if I hit save button without entering CustomerName then it is not showing error after save. It is showing error during oncomplete call and then navigating to view page, which I do not want.  Any help is appreciated. I have put a compiled code so that anyone can try with this code. What is polymorphism, what is it for, and how is it used?