Was this page helpful?
Your feedback about this content is important. Let us know what you think.
Additional feedback?
1500 characters remaining
Export (0) Print
Expand All
div
eof
Expand Minimize
Important This document may not represent best practices for current development, links to downloads and other resources may no longer be valid. Current recommended version can be found here.

sqrt, sqrtf 

Calculates the square root.


double sqrt(
   double x 
);
float sqrt(
   float x 
);  // C++ only
long double sqrt(
   long double x
);  // C++ only
float sqrtf(
   float x 
);

Parameters

x

Nonnegative floating-point value

C++ allows overloading, so users can call overloads of sqrt that take float or long double types. In a C program, sqrt always takes and returns double.

The sqrt function returns the square-root of x. If x is negative, sqrt returns an indefinite, by default.

Input SEH Exception Matherr Exception

± QNAN,IND

none

_DOMAIN

- ∞

INVALID

_DOMAIN

x>0

INVALID

_DOMAIN

Routine Required header Compatibility

sqrt, sqrtf

<math.h>

ANSI, Windows 95, Windows 98, Windows 98 Second Edition, Windows Millennium Edition, Windows NT 4.0, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003

For additional compatibility information, see Compatibility in the Introduction.

// crt_sqrt.c
// This program calculates a square root.

#include <math.h>
#include <stdio.h>
#include <stdlib.h>

int main( void )
{
   double question = 45.35, answer;

   answer = sqrt( question );
   if( question < 0 )
      printf( "Error: sqrt returns %.2f\n, answer" );
   else
      printf( "The square root of %.2f is %.2f\n", question, answer );
}

Output

The square root of 45.35 is 6.73

Community Additions

ADD
Show:
© 2015 Microsoft