@ and Sequence ( and /@ )

Question

list = { {a,b}, {c,d}, {e,g} }

How to efficiently get

{ f[a,b], f[c,d], f[e,g] }

I tried various combinations using @, /@ together with Sequence, like

f[Sequence[#]] /@ list

but no success.

Yeah, Apply to the 1st level. – Αλέξανδρος Ζεγγ Jun 15 '18 at 09:22 — Αλέξανδρος Ζεγγ, Jun 15 '18 at 09:22

score 7 · Answer 1 · answered Jun 14 '18 at 17:35

7

Turning a comment into an answer.

f@@@list

The long form of this is

Apply[f,list,{1}]

and it can be generalized to depth d by

Apply[f,list,{d}]

answered Jun 14 '18 at 17:35

Henrik Schumacher

score 4 · Answer 2 · answered Jun 14 '18 at 17:36

4

list = {{a, b}, {c, d}, {e, g}};

Apply[f, list, {1}]

Or short hand of this

f@@@list

Both gives

{ f[a,b], f[c,d], f[e,g] }

answered Jun 14 '18 at 17:36

OkkesDulgerci

score 3 · Answer 3 · answered Jun 14 '18 at 17:15

3

f[Sequence @@ #] & /@ list

Finally worked. But is this the best(most efficient) way?

answered Jun 14 '18 at 17:15

Chen Stats Yu

2

As Henrik commented, this is the best(most efficient) way f@@@list – OkkesDulgerci Jun 14 '18 at 17:31

score 1 · Answer 4 · answered Jun 14 '18 at 17:25

1

You can also do

Map[f[#[[1]], #[[2]]] &, list]
{f[a, b], f[c, d], f[e, g]}

Or more compactly:

f[#[[1]], #[[2]]] & /@ list

answered Jun 14 '18 at 17:25

Rudy Potter

4 Answers4