Objective-c arithmetic functions and constants represent

not change

constant Name	Description
M_pi	Pi (=π)
M_pi_2	1/2 of Pi (=Π/2)
M_pi_4	1/4 of Pi (=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

Name of function	Description
int rand ()	Random number generation. Cases Srand (Time (nil)); Initial random number initialization int val = rand ()%50; Random number between 0~49
int abs (int a)	Absolute value of an integer (example) int val = ABS (-8); →8 * Use fabs when floating-point numbers.
Double Fabs (Double A)	Absolute value of floating-point numbers (example) Double val = fabs (-12.345); →12.345 ※the whole number is used abs.
Double floor (Double a)	Returns the integer portion of a floating-point number (discarding a decimal point) (example) Double val = floor (12.345); →12.000
Double Ceil (double A);	Returns the integer portion of a floating-point number (discards the decimal point and enters 1 digits) (example) Double val = ceil (12.345); →13.000
Double Pow (double A, double b)	A's B-square (example) Double val = Pow (2, 3); →8
Double sqrt (double A)	Square root of a (example) Double val = sqrt (2); →1.41421356

Objective-c arithmetic functions and constants represent