Add a method for adding multiples of matrix rows with upper column bound

[eddie788]

Problem Description

The current method add_multiple_of_row adds a multiple of row j to row i, starting from a certain column index. We could end at a certain column index as well.

The same holds for add_multiple_of_column too.

Proposed Solution

Add a new method add_multiple_of_row_end and the corresponding Cython version, maybe something like this

def add_multiple_of_row_end(self, Py_ssize_t i, Py_ssize_t j, s, Py_ssize_t end_col):
    self.check_row_bounds_and_mutability(i, j)
    try:
        s = self._coerce_element(s)
        self.add_multiple_of_row_end_c(i, j, s, end_col)
    except TypeError:
        raise TypeError('[...]')


cdef add_mult_of_row_end_c(self, Py_ssize_t i, Py_ssize_t j, s, Py_ssize_t end_col):
    cdef Py_ssize_t c
    for c from 0 <= c <= end_col:
        self.set_unsafe(i, c, self.get_unsafe(i, c) + s*self.get_unsafe(j, c))

Alternatives Considered

This seems slightly faster than overloading the original add_multiple_of_row with an end_col parameter.

Additional Information

No response

Is there an existing issue for this?

• I have searched the existing issues for a bug report that matches the one I want to file, without success.