1.6 pattern example 1

Given list \(3,4,x,x^2,x^3\), find those elements of form \(x^n\) where \(n\) is anything other than \(1\).

In Maple

L:=[3,4,x,x^2,x^3]; 
map(X->`if`(patmatch(X,x^n::nonunit(anything)),X,NULL),L) 
 
     [x^2, x^3]
 

The above can also be written in the long form

restart; 
 
L:=[3,4,x,x^2,x^3]; 
 
map(proc(X) 
    if patmatch(X,x^n::nonunit(anything)) then 
       X; 
    else 
      NULL; 
    fi; 
    end proc,L) 
 
 
     [x^2, x^3]
 

In Mathematica

Cases[{3, 4, x, x^2, x^3}, x^_] 
 
          {x^2, x^3}