ccosf, ccos, ccosl
From cppreference.com
C
Concurrency support (C11)
Complex number arithmetic
Types and the imaginary constant
Manipulation
Power and exponential functions
Trigonometric functions
Hyperbolic functions
Defined in header
<complex.h>
Defined in header
<tgmath.h>
#define cos( z )
(4)
(since C99)
1-3) Computes the complex cosine of
z
.4) Type-generic macro: If
z
has type long double complex , ccosl
is called. if z
has type double complex , ccos
is called, if z
has type float complex , ccosf
is called. If z
is real or integer, then the macro invokes the corresponding real function (cosf, cos , cosl). If z
is imaginary, then the macro invokes the corresponding real version of the function cosh , implementing the formula cos(iy) = cosh(y), and the return type is real.[edit] Parameters
z
-
complex argument
[edit] Return value
If no errors occur, the complex cosine of z
is returned.
Errors and special cases are handled as if the operation is implemented by ccosh (I*z).
[edit] Notes
The cosine is an entire function on the complex plane, and has no branch cuts.
Mathematical definition of the cosine is cos z = eiz
+e-iz
+e-iz
2
[edit] Example
Run this code
#include <stdio.h> #include <math.h> #include <complex.h> int main(void) { double complex z = ccos(1); // behaves like real cosine along the real line printf ("cos(1+0i) = %f%+fi ( cos(1)=%f)\n", creal (z), cimag (z), cos (1)); double complex z2 = ccos(I); // behaves like real cosh along the imaginary line printf ("cos(0+1i) = %f%+fi (cosh(1)=%f)\n", creal (z2), cimag (z2), cosh (1)); }
Output:
cos(1+0i) = 0.540302-0.000000i ( cos(1)=0.540302) cos(0+1i) = 1.543081-0.000000i (cosh(1)=1.543081)
[edit] References
- C11 standard (ISO/IEC 9899:2011):
- 7.3.5.4 The ccos functions (p: 191)
- 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):
- 7.3.5.4 The ccos functions (p: 173)
- 7.22 Type-generic math <tgmath.h> (p: 335-337)
- G.7 Type-generic math <tgmath.h> (p: 480)
[edit] See also
C++ documentation for cos