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std::polar(std::complex)

From cppreference.com
< cpp‎ | numeric‎ | complex
Defined in header <complex>
template< class T >
complex<T> polar( const T& r, const T& theta = 0 );

Returns a complex number with magnitude r and phase angle theta.

The behavior is undefined if r is negative or NaN, or if theta is infinite (since C++17)

Parameters

r - magnitude
theta - phase angle

Return value

a complex number determined by r and theta

See also

returns the magnitude of a complex number
(function template)
returns the phase angle
(function template)