Math Constants
#define _USE_MATH_DEFINES // for C++
#include <cmath>
#define _USE_MATH_DEFINES // for C
#include <math.h>
Comentarios
The following symbols are defined for the values of their indicated expressions:
Symbol |
Expression |
Value |
|---|---|---|
M_E |
e |
2.71828182845904523536 |
M_LOG2E |
log2(e) |
1.44269504088896340736 |
M_LOG10E |
log10(e) |
0.434294481903251827651 |
M_LN2 |
ln(2) |
0.693147180559945309417 |
M_LN10 |
ln(10) |
2.30258509299404568402 |
M_PI |
pi |
3.14159265358979323846 |
M_PI_2 |
pi/2 |
1.57079632679489661923 |
M_PI_4 |
pi/4 |
0.785398163397448309616 |
M_1_PI |
1/pi |
0.318309886183790671538 |
M_2_PI |
2/pi |
0.636619772367581343076 |
M_2_SQRTPI |
2/sqrt(pi) |
1.12837916709551257390 |
M_SQRT2 |
sqrt(2) |
1.41421356237309504880 |
M_SQRT1_2 |
1/sqrt(2) |
0.707106781186547524401 |
Math Constants are not defined in Standard C/C++.To use them, you must first define _USE_MATH_DEFINES and then include cmath or math.h.
The file ATLComTime.h includes math.h when your project is built in Release mode.If you use one or more of the math constants in a project that also includes ATLComTime.h, you must define _USE_MATH_DEFINES before you include ATLComTime.h.