To use the complex or c_exception classes, you must either:
#include <complex.h>
The following table lists the mathematical constants that the Complex Mathematics Library defines.
| Constant Name | Description | |
| M_E | The constant e | |
| M_LOG2E | The logarithm of e to the base 2 | |
| M_LOG10E | The logrithm of e to the base 10 | |
| M_LN2 | The natural logrithm of 2 | |
| M_LN10 | The natural logrithm of 10 | |
| M_PI | pi | |
| M_PI_2 | pi divided by two | |
| M_PI_4 | pi divided by four | |
| M_1_PI | 1/pi | |
| M_2_PI | 2/pi | |
| M_2_SQRTPI | 2 divided by the square root of pi | |
| M_SQURT2 | The square root of 2 | |
| M_SQURT1_2 | The square root of 1/2 |