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	$log(e)$
$M_LN2	0.69314718055994530942	$ln(2)$
$M_LN10	2.30258509299404568402	$ln(10)$
$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	$1/\sqrt{2}$

Macro	Value	Equivalent to
$M_E	2.7182818284590452354	\(e\)
$M_LOG2E	1.4426950408889634074	\(log_2(e)\)
$M_LOG10E	0.43429448190325182765	\(log(e)\)
$M_LN2	0.69314718055994530942	\(ln(2)\)
$M_LN10	2.30258509299404568402	\(ln(10)\)
$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	\(1/\sqrt{2}\)