Description:  Derives the square root of the argument.  
Class:  Elemental function; Generic  
Arguments:  X must be of type real or complex. If X is type real, its value must be greater than or equal to zero.  
Results:  The result type is the same as X. The result has a value equal to the square root of X. A result of type complex is the principal value, with the real part greater than or equal to zero. When the real part of the result is zero, the imaginary part is greater than or equal to zero. 
Specific Name  Argument Type  Result Type 

SQRT  REAL(4)  REAL(4) 
DSQRT  REAL(8)  REAL(8) 
QSQRT  REAL(16)  REAL(16) 
CSQRT[1]  COMPLEX(4)  COMPLEX(4) 
CDSQRT[2]  COMPLEX(8)  COMPLEX(8) 
[1] The setting of compiler options specifying
real size can affect CSQRT.

Examples
SQRT (16.0) has the value 4.0.
SQRT (3.0) has the value 1.732051.