Expression of arithmetic functions and constants in objective-C

Constant

Constant name	Description
M_pi	Circumference rate (= π)
M_pi_2	1/2 of the circumference rate (= π/2)
M_pi_4	1/4 of the circumference rate (= π/4)
M_1_pi	= 1/π
M_2_pi	= 2/π
M_e	= E
M_log2e	Log_2 (E)
M_log10e	Log_10 (E)

Arithmetic functions

function name	description
int rand ()	random number generation. (example) srand (Time (NiL); // initial random number int val = rand () % 50; // 0 ~ Random Number between 49
int ABS (int A)	absolute value of an integer (example) int val = ABS (-8); → 8 ※fabs is used for Floating Point.
double FABS (double A)	absolute value of a floating point (for example, double val = FABS (-12.345); → 12.345 ※abs is used for integers.
double floor (double A)	return the integer part of the floating point number (discard the decimal point) (example) Double val = floor (12.345); → 12.000
double Ceil (double A);	return the integer part of the floating point number (discard the decimal part and Add 1 to the single digit) (example) Double val = Ceil (12.345); → 13.000
double POW (double A, double B)	B power of a (example) Double val = POW (2, 3); → 8
double SQRT (double A)	square root of a (example) Double val = SQRT (2); → 1.41421356

Expression of arithmetic functions and constants in objective-C