title: Matrix with gradient ranging from certain value to zero
body: <p>I want to create a matrix which has in its "lower left" corner it's maximum value (e.g. 10) and in the "lower right" and "upper left" corner 0 as its value. The matrix should be filled with values ranging from the maximum value to one and then with zeros. </p>
  
  <pre><code>##e.g. start with this
  m &lt;- matrix(ncol = 10, nrow = 10)
  m[,1] &lt;- 1:10
  m[10, ] &lt;- 10:1
  </code></pre>
  
  <p>What is the most efficient way to fill the matrix analogously to </p>
  
  <pre><code>## 1 0 0 0
  ## 2 1 0 0 
  ## 3 2 1 0
  ## 4 3 2 1 
  </code></pre>