6.40.29 Applying a bivariate function to the elements of two lists:
zip
The
zip
command applies a bivariate function to the elements of 2 lists.
zip
takes three arguments:
f
, a function of two variables.
L
1
and
L
2
, two lists of the same size
n
.
zip(
f
,
L
1
,
L
2
)
returns a list of size
n
whose
k
th element is
f
applied to the
k
th elements of
L
1
and
L
2
Examples.
Input:
zip(’sum’,[a,b,c,d],[1,2,3,4])
Output:
⎡
⎣
a
+1,
b
+2,
c
+3,
d
+4
⎤
⎦
Input:
zip((x,y)->x^2+y^2,[4,2,1],[3,5,1])
or:
f:=(x,y)->x^2+y^2
zip(f,[4,2,1],[3,5,1])
Output:
⎡
⎣
25,29,2
⎤
⎦
Input:
f:=(x,y)->[x^2+y^2,x+y]
zip(f,[4,2,1],[3,5,1])
Output:
⎡
⎢
⎢
⎣
25
7
29
7
2
2
⎤
⎥
⎥
⎦