sqrt, sqrtf, sqrtl
Visual Studio 2015
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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 ); long double sqrtl( long double x );
Parameters
x
Non-negative floating-point value
Because C++ allows overloading, you can call overloads of sqrt that take float or long double types. In a C program, sqrt always takes and returns double.
The sqrt functions return the square-root of x. By default, if x is negative, sqrt returns an indefinite NaN.
| Input | SEH Exception | _matherr Exception |
|---|---|---|
| ± QNAN,IND | none | _DOMAIN |
| - ∞ | none | _DOMAIN |
| x<0 | none | _DOMAIN |
| Function | C header | C++ header |
|---|---|---|
sqrt, sqrtf, sqrtl | <math.h> | <cmath> |
For compatibility information, see Compatibility.
// 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 %f\n", answer );
else
printf( "The square root of %.2f is %.2f\n", question, answer );
}
The square root of 45.35 is 6.73
Floating-Point Support
exp, expf
log, logf, log10, log10f
pow, powf, powl
_CIsqrt
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