Orchestra macros work like C preprocessor macros, and replace the content of the macro in the orchestra before it is compiled. The opcodes one can use to create, call, or undefine orchestra macros are:
Orchestra macros can also be defined using the command line flag --omacro:.
More information and examples on the usage of orchestra macros can be found in the entry for #define.
These opcodes refer to orchestra macros; for score macros, refer to Score Macros.
New in Csound 5.04 are predefined Math Constant Macros. The values defined are those found in the C header math.h, and are automatically defined when Csound starts and available for use in orchestras.
| Macro | Value | Equivalent to |
|---|---|---|
| $M_E | 2.7182818284590452354 | e |
| $M_LOG2E | 1.4426950408889634074 | log_2(e) |
| $M_LOG10E | 0.43429448190325182765 | log_10(e) |
| $M_LN2 | 0.69314718055994530942 | log_e(2) |
| $M_LN10 | 2.30258509299404568402 | log_e(10) |
| $M_PI | 3.14159265358979323846 | pi |
| $M_PI_2 | 1.57079632679489661923 | pi/2 |
| $M_PI_4 | 0.78539816339744830962 | pi/4 |
| $M_1_PI | 0.31830988618379067154 | 1/pi |
| $M_2_PI | 0.63661977236758134308 | 2/pi |
| $M_2_SQRTPI | 1.12837916709551257390 | 2/sqrt(pi) |
| $M_SQRT2 | 1.41421356237309504880 | sqrt(2) |
| $M_SQRT1_2 | 0.70710678118654752440 | 1/sqrt(2) |