cargf, carg, cargl
From cppreference.com
Defined in header <complex.h> | ||
float cargf(floatcomplex z ); | (1) | (since C99) |
double carg(doublecomplex z ); | (2) | (since C99) |
longdouble cargl(longdoublecomplex z ); | (3) | (since C99) |
Defined in header <tgmath.h> | ||
#define carg( z ) | (4) | (since C99) |
1-3) Computes the argument (also called phase angle) of
z, with a branch cut along the negative real axis.4) Type-generic macro: if
z has type longdoublecomplex, longdoubleimaginary, or longdouble, cargl is called. If z has type floatcomplex, floatimaginary, or float, cargf is called. If z has type doublecomplex, doubleimaginary, double, or any integer type, carg is called.Contents |
[edit]Parameters
| z | - | complex argument |
[edit]Return value
If no errors occur, returns the phase angle of z in the interval [−π; π].
Errors and special cases are handled as if the function is implemented as atan2(cimag(z), creal(z))
[edit]Example
Run this code
#include <stdio.h>#include <complex.h> int main(void){doublecomplex z1 =1.0+0.0*I;printf("phase angle of %.1f%+.1fi is %f\n", creal(z1), cimag(z1), carg(z1)); doublecomplex z2 =0.0+1.0*I;printf("phase angle of %.1f%+.1fi is %f\n", creal(z2), cimag(z2), carg(z2)); doublecomplex z3 =-1.0+0.0*I;printf("phase angle of %.1f%+.1fi is %f\n", creal(z3), cimag(z3), carg(z3)); doublecomplex z4 =conj(z3);// or CMPLX(-1, -0.0)printf("phase angle of %.1f%+.1fi (the other side of the cut) is %f\n", creal(z4), cimag(z4), carg(z4));}
Output:
phase angle of 1.0+0.0i is 0.000000 phase angle of 0.0+1.0i is 1.570796 phase angle of -1.0+0.0i is 3.141593 phase angle of -1.0-0.0i (the other side of the cut) is -3.141593
[edit]References
- C11 standard (ISO/IEC 9899:2011):
- 7.3.9.1 The carg functions (p: 196)
- 7.25 Type-generic math <tgmath.h> (p: 373-375)
- G.7 Type-generic math <tgmath.h> (p: 545)
- C99 standard (ISO/IEC 9899:1999):
- 7.3.9.1 The carg functions (p: 178)
- 7.22 Type-generic math <tgmath.h> (p: 335-337)
- G.7 Type-generic math <tgmath.h> (p: 480)
[edit]See also
(C99)(C99)(C99) | computes the magnitude of a complex number (function) |
(C99)(C99) | computes arc tangent, using signs to determine quadrants (function) |
C++ documentation for arg | |
