sqrt(3M)

NAME

     sqrt - square root function

SYNOPSIS

     cc [ flag ... ] file ... -lm [ library ... ]
     #include <math.h>

     double sqrt(double x);

DESCRIPTION

     The sqrt() function computes the square root of x.

RETURN VALUES

     Upon successful completion, sqrt() returns the  square  root
     of x.

     If x is NaN, NaN is returned.

     If x is negative, NaN is returned and errno is set to EDOM.

ERRORS

     The sqrt() function will fail if:

     EDOM  The value of x is negative.

USAGE

     An application wishing to check for error situations  should
     set  errno  to 0 before calling sqrt(). If errno is non-zero
     on return,  or  the  return  value  is  NaN,  an  error  has
     occurred.

ATTRIBUTES

     See attributes(5) for descriptions of the  following  attri-
     butes:

     ____________________________________________________________
    |       ATTRIBUTE TYPE        |       ATTRIBUTE VALUE       |
    |_____________________________|_____________________________|
    | MT-Level                    | MT-Safe                     |
    |_____________________________|_____________________________|

SEE ALSO

     isnan(3M), attributes(5)