I am new to Ubuntu and i want to install iTunes through playOnLinux.. Every time I open playOnLinux though , i get the following error :   PlayOnLinux is unable to find 32bits OpenGL libraries. You might encounter problem with your games   and then this error :   PlayOnLinux cannot find wine (from Wine) You should install it to use PlayOnLinux   My ubuntu version is 16.04..  What I'm supposed to do ??
I am looking for a step by step instruction to guide me in the ways of installing, configuring and debugging many of the issues new users have when dealing with Wine in Ubuntu.  What is the recommended way of installing Wine, some of the key issues that it has and how to solve them?  If I have a specific problem with an App in Wine, how do I go about solving it? What are the recommended steps to ensure that I can fix a problem related to an app I wish to use?
Excluding grep from process list (Note that I have used bold text frequently simply to highlight the key points of my question for those who do not have the time to read through it thoroughly (it is not very long, however); I hope this is not considered offensive.)  There are many textbooks on multivariable calculus. However, some textbooks on multivariable calculus do not focus very much on the theoretical foundations of the subject. For example, a textbook might state a result along the lines of "the order of partial differentiation is immaterial" without proof and ask the student to use this rule to solve problems. Similarly, theorems such as those due to Green and Stokes are often not proved in their full generality.   Therefore, I ask the following question:      What are some good theoretical   multivariable calculus textbooks?   Since "theoretical" is somewhat ambiguous, let me state the following criteria which I would like a "theoretical" textbook on multivariable calculus to satisfy:   The textbook should be rigorous and it should not state a theorem without proof if the theorem is proved in at least one other multivariable calculus textbook. (Of course, the textbook may omit certain theorems; however, this criterion at least ensures that major theorems in multivariable calculus are not stated without proof and used purely for the sake of computations. Also, this criterion permits the textbook to state an interesting theorem if it is beyond the scope of all multivariable calculus textbooks.) The textbook should be primarily based on developing the theoretical foundations of multivariable calculus; therefore, applications such as learning how to compute the partial derivative of a function, learning how to solve extremum problems, learning how to compute etc. should be kept to a minimum. In particular, the textbook can assume that the reader has already seen at least an informal treatment of the subject where these aspects are emphasized. The textbook should have a rigorous treatment of differentiability in $n$-dimensional Euclidean space (e.g., the inverse and implicit function theorems should be proven), Riemann integration in $n$-space, and differential forms (e.g., Stokes theorem should be proven). It would also be a bonus if the book treated the general concept of a manifold. Textbooks with minimal prerequisites are preferred; however, please feel free to suggest books meeting the above criteria even if the prerequisites are quite demanding. Finally, it would also be preferable, but not essential, for the book to only treat multivariable calculus.   Examples of books meeting the above criteria: "Analysis on Manifolds" by James Munkres, "Principles of Mathematical Analysis" by Walter Rudin, and "Calculus on Manifolds" by Michael Spivak.   Although I have studied theoretical multivariable calculus already (four years ago), I could never find "the perfect book" (relative to myself, of course). Every book has its virtues; Rudin for its elegance, Munkres for its beautiful exposition, and Spivak for its "quick and dirty" approach. I am hoping that someone will be able to suggest a book that (relative to myself) is "perfect". Also, this question can be useful to other students who have not yet studied the subject and wish to learn it.   Thank you very much for all answers! Please do feel free to suggest as many books as you can think of so we can form a big list. Also, please try to explain why a particular book is good or at least why you think it is good. I suppose it is fine to suggest a book that is already suggested provided you have a different view as to why the book is good. Why are the Degrees of Freedom for multiple regression n - k - 1? For linear regression, why is it n - 2? I'm reading a textbook and I see this question:    So there are 200 women, and the DF is 196, implying that the equation for DF is $n - k - 1$. There are 3 variables: bp, age, and type so $k == 3$. What's the intuition behind this?  Also, why is the degrees of freedom for linear regression n - 2? Been trying to this line to parse for a good 20mins, but all attempts have failed:  \beta = $-$0.84, t = $-$2.09, P = 0.04   Could anyone tell me why I'm getting a Missing $ inserted error here? Cardinality of the set of all real functions of real variable How does one compute the cardinality of the set of functions $f:\mathbb{R} \to \mathbb{R}$ (not necessarily continuous)? How to run scripts without typing the full path? I'd like to know if there is a way to run  program/shell script without typing full path:  /opt/idea/bin/idea.sh I accidentally killed a noble, now every guard wants to kill me. Is there any way I can get rid of the bounty? Regular expression to match DNS hostname or IP Address? How can I add four spaces before each lines of programs code in terminal How to number and cross-reference \subsubsection-level headers Explanation that air drag is proportional to speed or square speed? How can I install Windows after I've installed Ubuntu? I have Ubuntu on my laptop. Now I want install Windows 7 in a dual-boot. How can I do this? I can't lose my Ubuntu files, and I'm afraid that I might break . Go  for UEFI only! Only squares instead of letters and numbers are displayed in my calculator and other apps in Ubuntu 18.04 Beamer: change header background color I have decided to switch from Powerpoint to Beamer, and for my first presentation I'd like to use the , and the same colors as in this goggle slide template:  .  I tried to do some research about it, the closest answers I found are the question  and the . I tried this code:  \documentclass{beamer} \usepackage[frenchb]{babel} \usepackage[T1]{fontenc} \usepackage[utf8]{inputenc}  \usetheme{metropolis}  \definecolor{bluegreen}{rgb}{3, 166, 155} \definecolor{pitchblack}{rgb}{0, 0, 0} \definecolor{lightbeige}{rgb}{255, 251, 241} \definecolor{mediumgray}{rgb}{183, 183, 183}  \setbeamercolor{background canvas}{bg=pitchblack} \setbeamercolor{normal text}{fg=lightbeige} \setbeamercolor{headline}{bg=bluegreen, fg=mediumgray}  \begin{document} \begin{frame}     \frametitle{The title}     Lorem ipsum... \end{frame} \end{document}   I does everything I want, except that the title bar's background color is lightbeige:    What did I do wrong? Or what argument should I pass to \setbeamercolor to get it right? Thanks in advance :-). Capitalization of the word "the" in "the Lord" / "The Lord" Should I capitalize the word "the" when speaking of God as "the/The Lord"?     I praise the Lord.   or...     I praise The Lord. Communities list is counting my reputation wrong on some sites I have 101 rep on  and am not suspended there. But the site switcher thinks I only have 1 rep there:     I noticed this after I .   To test this, I just added Expats and Reverse Engineering to my site switcher list. On both of those sites I have 101 rep and am not suspended. Results:    Huh? How does Motherboard and CPU affect RAM choice? Why can't I left click on my Macbook Pro? Random weighted choice Consider the class below that represents a Broker:  public class Broker {     public string Name = string.Empty;     public int Weight = 0;      public Broker(string n, int w)     {         this.Name = n;         this.Weight = w;     } }   I'd like to randomly select a Broker from an array, taking into account their weights.  What do you think of the code below?  class Program     {         private static Random _rnd = new Random();          public static Broker GetBroker(List&lt;Broker&gt; brokers, int totalWeight)         {             // totalWeight is the sum of all brokers' weight              int randomNumber = _rnd.Next(0, totalWeight);              Broker selectedBroker = null;             foreach (Broker broker in brokers)             {                 if (randomNumber &lt;= broker.Weight)                 {                     selectedBroker = broker;                     break;                 }                  randomNumber = randomNumber - broker.Weight;             }              return selectedBroker;         }           static void Main(string[] args)         {             List&lt;Broker&gt; brokers = new List&lt;Broker&gt;();             brokers.Add(new Broker("A", 10));             brokers.Add(new Broker("B", 20));             brokers.Add(new Broker("C", 20));             brokers.Add(new Broker("D", 10));              // total the weigth             int totalWeight = 0;             foreach (Broker broker in brokers)             {                 totalWeight += broker.Weight;             }              while (true)             {                 Dictionary&lt;string, int&gt; result = new Dictionary&lt;string, int&gt;();                  Broker selectedBroker = null;                  for (int i = 0; i &lt; 1000; i++)                 {                     selectedBroker = GetBroker(brokers, totalWeight);                     if (selectedBroker != null)                     {                         if (result.ContainsKey(selectedBroker.Name))                         {                             result[selectedBroker.Name] = result[selectedBroker.Name] + 1;                         }                         else                         {                             result.Add(selectedBroker.Name, 1);                         }                     }                 }                   Console.WriteLine("A\t\t" + result["A"]);                 Console.WriteLine("B\t\t" + result["B"]);                 Console.WriteLine("C\t\t" + result["C"]);                 Console.WriteLine("D\t\t" + result["D"]);                  result.Clear();                 Console.WriteLine();                 Console.ReadLine();             }         }     }   I'm not so confident. When I run this, Broker A always gets more hits than Broker D, and they have the same weight.  Is there a more accurate algorithm?  Thanks! When is it acceptable to call GC.Collect? The general advise is that you should not call GC.Collect from your code, but what are the exceptions to this rule?  I can only think of a few very specific cases where it may make sense to force a garbage collection.   One example that springs to mind is a service, that wakes up at intervals, performs some task, and then sleeps for a long time. In this case, it may be a good idea to force a collect to prevent the soon-to-be-idle process from holding on to more memory than needed.   Are there any other cases where it is acceptable to call GC.Collect?