title: 3D surface plot from 2D matrix
body: <p>Using a 2d matrix in R, how can I create a 3d surface plot, where columns=x, rows=y and the values are the heights in z?</p>
  
  <p>In the example below, x values would be 1:5, y value would be 1:5, and the numbers would represent heights/values in z.</p>
  
  <pre><code>&gt; m&lt;-matrix(rnorm(25),nrow=5,ncol=5)
  &gt; m
               [,1]       [,2]       [,3]        [,4]       [,5]
  [1,] -1.495513045  0.8000040 -1.1499261  1.65661138  0.8140510
  [2,] -1.150018195 -0.7582933  0.8306922  0.16026908  0.3913198
  [3,] -0.852609406  0.5525621  0.3585986 -0.45054768 -1.2259927
  [4,] -0.001926297 -0.5857351  2.1518281  0.03192463  0.2065039
  [5,] -1.641128610  0.4333973 -1.0616628 -0.92143426 -0.9598991
  </code></pre>