docs: public static boolean isSkewSymmetric(DMatrixRMaj A , double tol ){
          if( A.numCols != A.numRows )
              return false;
  
          for( int i = 0; i < A.numRows; i++ ) {
              for( int j = 0; j < i; j++ ) {
                  double a = A.get(i,j);
                  double b = A.get(j,i);
  
                  double diff = Math.abs(a+b);
  
                  if( !(diff <= tol) ) {
                      return false;
                  }
              }
          }
          return true;
      }