range method
Returns a mutable view onto the row and column ranges. Throws a RangeError, if any of the ranges are out of bounds.
Implementation
Matrix<T> range(int rowStart, int rowEnd, int columnStart, int columnEnd) {
rowEnd = RangeError.checkValidRange(
rowStart, rowEnd, rowCount, 'rowStart', 'rowEnd');
columnEnd = RangeError.checkValidRange(
columnStart, columnEnd, colCount, 'columnStart', 'columnEnd');
return rangeUnchecked(rowStart, rowEnd, columnStart, columnEnd);
}