connect two pixels

Connect two pixels in a matrice/image.

I think the created line is the most sort as it can be but if not tell me yours ideas :)

Command line
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result=linept2(matrice, X1, Y1, X2, Y2)
matrice : matrice where I'll write
(X1, Y1), (X2, Y2) : points to connect
result : matrix + the line

Note
----
matrice can contents anything
(X1, Y1), (X2, Y2) can be out of the matrice

Example
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a = linept(zeros(5, 10), 2, 2, 3, 9)
a =
0 0 0 0 0 0 0 0 0 0
0 1 1 1 1 0 0 0 0 0
0 0 0 0 0 1 1 1 1 0
0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0