floor(x) is the greatest integer less than or equal to x.

The floor(M) function computes the element-wise floor of M.  The result, R, is formed as R[i,j] = floor(M[i,j]).

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

$M≔\mathrm{Matrix}\left(2\,3\,'\mathrm{fill}'=-3.6\right)\:$

$\mathrm{floor}\left(M\right)$

$\left[\begin{array}{ccc}\mathrm{-4}& \mathrm{-4}& \mathrm{-4}\\ \mathrm{-4}& \mathrm{-4}& \mathrm{-4}\end{array}\right]$