std::cos(std::complex)
From cppreference.com
| Defined in header <complex>
|
||
| template< class T > complex<T> cos( const complex<T>& z ); |
||
Computes complex cosine of a complex value z.
Parameters
| z | - | complex value |
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 std::cosh(i * z), where i is the imaginary unit.
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 |
| 2 |
Example
Run this code
#include <cmath> #include <complex> #include <iostream> int main() { std::cout << std::fixed; std::complex<double> z(1.0, 0.0); // behaves like real cosine along the real line std::cout << "cos" << z << " = " << std::cos(z) << " ( cos(1) = " << std::cos(1) << ")\n"; std::complex<double> z2(0.0, 1.0); // behaves like real cosh along the imaginary line std::cout << "cos" << z2 << " = " << std::cos(z2) << " (cosh(1) = " << std::cosh(1) << ")\n"; }
Output:
cos(1.000000,0.000000) = (0.540302,-0.000000) ( cos(1) = 0.540302) cos(0.000000,1.000000) = (1.543081,-0.000000) (cosh(1) = 1.543081)
See also
| computes sine of a complex number (sin(z)) (function template) | |
| computes tangent of a complex number (tan(z)) (function template) | |
| (C++11) |
computes arc cosine of a complex number (arccos(z)) (function template) |
| (C++11)(C++11) |
computes cosine (cos(x)) (function) |
| applies the function std::cos to each element of valarray (function template) | |
| C documentation for ccos
| |