title: Purpose of LDA argument in BLAS dgemm?
body: <p>The Fortran reference implementation documentation states:</p>
  
  <pre><code>*  LDA    - INTEGER.
  *           On entry, LDA specifies the first dimension of A as declared
  *           in the calling (sub) program. When  TRANSA = 'N' or 'n' then
  *           LDA must be at least  max( 1, m ), otherwise  LDA must be at
  *           least  max( 1, k ).
  *           Unchanged on exit.
  </code></pre>
  
  <p>However, given m and k shouldn't I be able to derive LDA?  When is LDA permitted to be bigger than n (or k)?</p>