Can i use s insted sin()?

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I have a long long formula, like

float a = sin(b)*cos(c)+sin(c+d)*sin(d)....

Is there a way to use s instead sin in C programming, to shorten the formula, without affecting the running time?


if I use define, does it affect runtime?

define works by doing text-based substitution at compile time. If you #define s(x) sin(x) then the C pre-processor will rewrite all the s(x) into sin(x) before the compiler gets a chance to look at it.

BTW, this kind of low-level text-munging is exactly why define can be dangerous to use for more complex expressions. For example, one classic pitfall is that if you do something like #define times(x, y) x*y then times(1+1,2) rewrites to 1+1*2, which evaluates to 3 instead of the expected 4. For more complex expressions like it is often a good idea to use inlineable functions instead.


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