title: Correctly Importing Apache Commons Math Package
body: <p>I am trying to use the SimplexSolver class in the Apache Commons Math package, but I can't seem to import the package correctly; all of the following is happening in a fixed directory called 'Java'.  I downloaded commons-math3-3.1.1 and put the unzipped folder into the 'Java' directory.</p>
  
  <p>Here is some example code, HelloWorld.java, saved in the 'Java' directory:</p>
  
  <pre><code>import org.apache.commons.math;
  
  public class HelloWorld {
          public static void main (String[] args) {
                  System.out.println("Hello World!");
                  }
  }
  </code></pre>
  
  <p>I then proceed to type the following command into the terminal:</p>
  
  <pre><code>javac -cp ./commons-math3-3.1.1/commons-math3-3.1.1.jar:. HelloWorld.java
  </code></pre>
  
  <p>And I am greeted with the following error:</p>
  
  <pre><code>HelloWorld.java:1: package org.apache.commons does not exist
  import org.apache.commons.math;
                           ^
  1 error
  </code></pre>
  
  <p>I'm sure I'm misunderstanding the correct way to import downloaded packages, and any help would be greatly appreciated.  I've tried variants of the import line, such as import org.apache.commons.math.*; and things like that, but none of them have worked so far.</p>
  
  <p>Thanks in advance!</p>