std::arg(std::complex)
Defined in header <complex> |
||
|---|---|---|
template< class T > T arg( const complex<T>& z ); |
(1) | |
long double arg( long double z ); |
(2) | (since C++11) |
template< class DoubleOrInteger > double arg( DoubleOrInteger z ); |
(3) | (since C++11) |
float arg( float z ); |
(4) | (since C++11) |
Calculates the phase angle (in radians) of the complex number z.
| Additional overloads are provided for |
(since C++11) |
Parameters
| z | - | complex value |
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 std::atan2(std::imag(z), std::real(z)).
Example
#include <iostream>
#include <complex>
int main()
{
std::complex<double> z1(1, 0);
std::cout << "phase angle of " << z1 << " is " << std::arg(z1) << '\n';
std::complex<double> z2(0, 1);
std::cout << "phase angle of " << z2 << " is " << std::arg(z2) << '\n';
std::complex<double> z3(-1, 0);
std::cout << "phase angle of " << z3 << " is " << std::arg(z3) << '\n';
std::complex<double> z4(-1, -0.0);
std::cout << "phase angle of " << z4 << " (the other side of the cut) is "
<< std::arg(z4) << '\n';
}
Output:
phase angle of (1,0) is 0 phase angle of (0,1) is 1.5708 phase angle of (-1,0) is 3.14159 phase angle of (-1,-0) (the other side of the cut) is -3.14159
See also
| returns the magnitude of a complex number (function template) |
|
| constructs a complex number from magnitude and phase angle (function template) |
|
|
(C++11)(C++11)
|
arc tangent, using signs to determine quadrants (function) |
applies the function std::atan2 to a valarray and a value (function template) |
|
C documentation for carg |
|
© cppreference.com
Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.
https://en.cppreference.com/w/cpp/numeric/complex/arg
