std::sqrt(std::complex)
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                    |   Defined in header <complex>
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|   template< class T >  complex<T> sqrt( const complex<T>& x );  | 
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Computes the square root of the complex number x. 
The branch cuts are along the negative real axis.  sqrt computes the square root in the range of the right half-plane.  If x is a negative real number, the return value will lie on the positive imaginary axis.
[edit] Parameters
| x | - | complex number to take the square root of | 
[edit] Return value
the square root of x.
[edit] See also
|    complex power, one or both arguments may be a complex number   (function template)  | |