Mathematical Library Functions                          hypot(3M)



NAME
     hypot, hypotf, hypotl - Euclidean distance function

SYNOPSIS
     c99 [ flag... ] file... -lm [ library... ]
     #include 

     double hypot(double x, double y);


     float hypotf(float x, float y);


     long double hypotl(long double x, long double y);


DESCRIPTION
     These functions compute the length of the square root of x^2
     ] y^2 without undue overflow or underflow.

RETURN VALUES
     Upon  successful  completion,  these  functions  return  the
     length  of  the  hypotenuse  of a right angled triangle with
     sides of length x^2 and y^2.


     If the correct value would cause  overflow,  a  range  error
     occurs  and hypot(), hypotf(), and hypotl() return the value
     of the macro HUGEVAL,  HUGEVALF,  and  HUGEVAL,  respec-
     tively.


     If x or y is ]Inf, ]Inf is returned even if one of x or y is
     NaN.


     If x or y is NaN and  the  other  is  not  ]Inf,  a  NaN  is
     returned.

ERORS
     These functions will fail if:

     Range Error    The result overflows.

                    If the integer expression (matherrhandling &
                    MATHEREXCEPT)  is  non-zero,  the  overflow
                    floating-point exception is raised.


USAGE
     hypot(x,y), hypot(y,x), and hypot(x, -y) are equivalent.




SunOS 5.11           Last change: 1 Sep 2002                    1






Mathematical Library Functions                          hypot(3M)



     hypot(x, ]0) is equivalent to fabs(x).


     These functions  takes  precautions  against  underflow  and
     overflow during intermediate steps of the computation.


     An application wanting to check for exceptions  should  call
     feclearexcept(FEALEXCEPT) before calling these functions.
     On  return,  if  fetestexcept(FEINVALID    FEDIVBYZERO  
     FEOVERFLOW    FEUNDERFLOW)  is non-zero, an exception has
     been raised. An application should either examine the return
     value  or check the floating point exception flags to detect
     exceptions.

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



     
           ATRIBUTE TYPE               ATRIBUTE VALUE       
    
     Interface Stability          Standard                    
    
     MT-Level                     MT-Safe                     
    


SEE ALSO
     fabs(3M),  feclearexcept(3M),  fetestexcept(3M),  isnan(3M),
     math.h(3HEAD), sqrt(3M), attributes(5), standards(5)






















SunOS 5.11           Last change: 1 Sep 2002                    2