Consider a list of functions

M[x_]:={Cos[x], Sin[x], x}

Say I want to evaluate the first element


What Mathematica does is evaluate the entire list at x=1 then extracts the first element Cos[1]. For large list and complicated functions, this is costly as I don't need the rest of the list's elements(for now). Is there a way where I can make Mathematica extract the first element first, then evaluate it at x=1 instead of the other way around?


migrated from math.stackexchange.com Jun 18 '18 at 10:11

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ClearAll[m, m2]

Turn your already defined function that returns a list

m[x_] := {Cos[x], Sin[x], x}

to a list of functions:

m2 = Function /@ m[#];

Extract any part using Part ([[.]]) and use it with the desired input:






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