code: function subMatrix (data, numRows, numCols, row, col) {
    var sub = []
  
    for (var i = 0; i < numRows; i++) {
      for (var j = 0; j < numCols; j++) {
        if ((i !== row) && (j !== col)) {
          sub.push(data[matrixToArrayIndex(i, j, numCols)])
        }
      }
    }
  
    return sub
  }
docs: Compute the sub-matrix formed by deleting the i-th row and j-th column
  
  @function
  
  @param {Array} data set
  @param {Number} numRows
  @param {Number} numCols
  @param {Number} row index deleted
  @param {Number} col index deleted
  
  @returns {Array} sub data-set