throw away misleading feature size

Author: rwieruch

src/index.js

@@ -23,7 +23,6 @@ function init(matrix) {
   });
 
   let m = getDimensionSize(y, 1);
-  let n = getDimensionSize(y, 2);
 
   // Part 1: Feature Normalization
   console.log('Part 1: Feature Normalization ...\n');