Mathematica mat ={{2,4,3}, {7,9,5}, {0,5.4,9}} m = Max[mat]; (*this gives values *) Position[mat,m](*this find locations*)

Out[142]= {{2,2},{3,3}} 
Maple This below ﬁnds position of ﬁrst max. A:=Matrix([[2,4,3],[7,9,5],[0,5.4,9]]); v:=max(A); member(v,A,'pos'); pos

2,2 
Maple support for such operations seems to be not as strong as Matlab. One way to ﬁnd locations of all elements is by using explicit loop
A:=Matrix([[2,4,3],[7,9,5],[0,5.4,9]]); v:=max(A); r:=[seq(seq(`if`(A[i,j]=v,[i,j],NULL),i=1..3),j=1..3)];

[[2, 2], [3, 3]] 