Compile¶

Compiles a function for numerical evaluation.

$ wo 'sqr = Compile[{x}, x x]; sqr[2]'
4.

An undeclared argument defaults to _Real, which is why the result above is inexact. A declared _Integer argument binds an integer:

$ wo 'Compile[{{n, _Integer, 0}}, Nest[# + 1 &, 0, n]][4]'
4

A signature that includes a real works in machine reals throughout, so exact numbers from the body come back inexact:

$ wo 'Compile[{{x, _Real, 0}}, Clip[x, {-4, 4}]][-5.]'
-4.

A rank-n _Real argument is converted element by element:

$ wo 'Compile[{{g, _Real, 2}}, g][{{1, 1/2}, {3, 4}}]'
{{1., 0.5}, {3., 4.}}

Trailing option rules such as RuntimeAttributes and RuntimeOptions are accepted and don't change the result:

$ wo 'Compile[{{x, _Real}}, x^2, RuntimeAttributes -> {Listable}, RuntimeOptions -> "Speed"][3.]'
9.