IsTrapezoidal

Check if a rectangular (not square) m-by-n matrix is upper or lower trapezoidal.

Parameters

is_upper

[out]  Value specifies upper or lower trapezoidal matrix is recognized.

Return Value

True if matrix is trapezoidal.

Note

Zero matrix of m-by-n size is trapezoidal.

If m < n then check whether lower triangular part under the main diagonal contains all zeros. Zero matrix of 6-by-7 size is upper trapezoidal.

If m > n then check whether upper triangular part above the main diagonal contains all zeros. Zero matrix of 7-by-6 size is lower trapezoidal.

Trapezoidal matrices