title: Count elements in a vector of vectors in clojure
body: <p>If I have a matrix defined as:</p>
  
  <pre><code>(def m1 [[1 2 3][4 5 6][7 8 9]])
  </code></pre>
  
  <p>How do I go about counting the vectors within the vector in clojure. I know that (count m1) will return 3 which is the number of vectors I have in the initial vector but I can't remember how to count the inner vectors (its been a very very long time since I've had to deal with any lisp dialect). Also I do not want to flatten the vector and then count it because I need to count the values separately (ie. I want to return 3, 3, 3 because each of the inner vectors have 3 elements. One last restriction I guess is that I want to do this without using map right away because I realized I can simply do (map count m1).</p>