C in a Nutshell

Name

hypot

Synopsis

Calculates a hypotenuse by the Pythagorean formula

#include <math.h>
doublehypot( double x, double y );
float hypotf( float x, float y );
long double hypotl( long double x, long double y );

The hypot() functions compute the square root of the sum of the squares of their arguments, while avoiding intermediate overflows. If the result exceeds the function’s return type, a range error may occur.

Example

double x, y, h;            // Three sides of a triangle

printf( "How many kilometers do you want to go westward? " );
scanf( "%lf", &x );

printf( "And how many southward? " );
scanf( "%lf", &y );

errno = 0;
h = hypot( x, y );

if ( errno )
  perror( _  _FILE_  _ );
else
  printf( "Then you'll be %4.2lf km from where you started.\n", h );

If the user answers the prompts with 3.33 and 4.44, the program prints this output:

Then you'll be 5.55 km from where you started.

See Also

sqrt(), cbrt(), csqrt()