# Math functions

**double pow ( double, double ) **– power of

NSLog(@"%.f", pow(3,2) ); //result 9 NSLog(@"%.f", pow(3,3) ); //result 27

**double sqrt( double ) **– square root

NSLog(@"%.f", sqrt(16) ); //result 4 NSLog(@"%.f", sqrt(81) ); //result 9

**double ceil ( double ) **– if the argument has any decimal part, returns the next bigger integer

NSLog(@"res: %.f", ceil(3.000000000001)); //result 4 NSLog(@"res: %.f", ceil(3.00)); //result 3

**double floor ( double ) **– removes the decimal part of the argument

NSLog(@"res: %.f", floor(3.000000000001)); //result 3 NSLog(@"res: %.f", floor(3.9999999)); //result 3

**double round ( double ) **– rounds the argument

NSLog(@"res: %.f", round(3.5)); //result 4 NSLog(@"res: %.f", round(3.46)); //result 3 NSLog(@"res: %.f", round(-3.5)); //NB: this one returns -4

**double fmin ( double, double ) **– returns the smaller argument

NSLog(@"res: %.f", fmin(5,10)); //result 5

**double fmax ( double, double ) **– returns the bigger argument

NSLog(@"res: %.f", fmax(5,10)); //result 10

**double fabs( double ) **– returns the absolute value of the argument

NSLog(@"res: %.f", fabs(10)); //result 10 NSLog(@"res: %.f", fabs(-10)); //result 10

Eventually you will find also all the trigonometry you’ll need as: sin, cos, tan, atan, and their variations.

# Few math constants

As found in the math.h

#define M_E 2.71828182845904523536028747135266250 /* e */ #define M_LOG2E 1.44269504088896340735992468100189214 /* log 2e */ #define M_LOG10E 0.434294481903251827651128918916605082 /* log 10e */ #define M_LN2 0.693147180559945309417232121458176568 /* log e2 */ #define M_LN10 2.30258509299404568401799145468436421 /* log e10 */ #define M_PI 3.14159265358979323846264338327950288 /* pi */ #define M_PI_2 1.57079632679489661923132169163975144 /* pi/2 */ #define M_PI_4 0.785398163397448309615660845819875721 /* pi/4 */ #define M_1_PI 0.318309886183790671537767526745028724 /* 1/pi */ #define M_2_PI 0.636619772367581343075535053490057448 /* 2/pi */ #define M_2_SQRTPI 1.12837916709551257389615890312154517 /* 2/sqrt(pi) */ #define M_SQRT2 1.41421356237309504880168872420969808 /* sqrt(2) */ #define M_SQRT1_2 0.707106781186547524400844362104849039 /* 1/sqrt(2) */ #define MAXFLOAT ((float)3.40282346638528860e+38)

So, this is a wrap up for the overview of Objective-C math, if I missed the one function you use the most, feel free to leave a comment and share it with the other readers.

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