Orchestra Macros

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.

Predefined Math Constant 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)