The command ElementwiseOr(M1,M2) performs an element-wise comparison of M1 and M2.

For matrices M1 and M2, the result R is a matrix where  R[i,j] = 1, if either M1[i,j] or M2[i,j] is non-zero, and R[i,j] = 0 otherwise.

For matrix M1 and scalar M2, the result R is a matrix where  R[i,j] = 1, if either M1[i,j] or M2 is non-zero, and R[i,j] = 0 otherwise.

For scalar M1 and matrix M2, the result R is a matrix where  R[i,j] = 1, if either M1 or M2[i,j] is non-zero, and R[i,j] = 0 otherwise.

For scalars M1 and M2, the result R = 1, if either M1 or M2 is non-zero, R = 0 otherwise.

M1 and M2 must be the same size, or scalars.  

$\mathrm{with}\left(\mathrm{MTM}\right)\:$

$\mathrm{M1}≔\mathrm{Matrix}\left(\left[\left[1\,0\right]\,\left[0\,4\right]\right]\right)\:$

$\mathrm{M2}≔\mathrm{Matrix}\left(\left[\left[-1\,0\right]\,\left[3\,0\right]\right]\right)\:$

$\mathrm{ElementwiseOr}\left(\mathrm{M1}\,\mathrm{M2}\right)$

$\left[\begin{array}{cc}1& 0\\ 1& 1\end{array}\right]$

$\mathrm{M1}≔\mathrm{Matrix}\left(\left[\left[1\,0\right]\,\left[0\,4\right]\right]\right)\:$

$\mathrm{ElementwiseOr}\left(\mathrm{M1}\,3\right)$

$\left[\begin{array}{cc}1& 1\\ 1& 1\end{array}\right]$