code: public static double elementMinAbs( DMatrix2x2 a ) {
          double min = Math.abs(a.a11);
          double tmp = Math.abs(a.a12); if( tmp < min ) min = tmp;
          tmp = Math.abs(a.a21); if( tmp < min ) min = tmp;
          tmp = Math.abs(a.a22); if( tmp < min ) min = tmp;
  
          return min;
      }
docs: <p>
  Returns the absolute value of the element in the matrix that has the smallest absolute value.<br>
  <br>
  Min{ |a<sub>ij</sub>| } for all i and j<br>
  </p>
  
  @param a A matrix. Not modified.
  @return The max element value of the matrix.