sqrt(3m) — RISC
Name
cbrt, sqrt − cube root, square root
Syntax
#include <math.h>
double cbrt(x)
double x;
double sqrt(x)
double x;
float fsqrt(float x)
float x;
Description
The cbrt function returns the cube root of x.
The sqrt and fsqrt functions return the square root of x for double and float data types respectively.
A declaration of
float fsqrt(float)
is required to obtain correct results in a nonstandard compile.
Error Due to Roundoff and Other Reasons
The cbrt function is accurate to within 0.7 ulps.
The sqrt function on this machine conforms to IEEE 754 and is correctly rounded in accordance with the rounding mode in force; the error is less than half an ulp in the default mode (round−to−nearest). An ulp is one Unit in the Last Place carried.
Diagnostics
Both sqrt and fsqrt functions set errno to EDOM when the result is NaN.
The sqrt function returns the default quiet NaN when x is negative indicating the invalid operation.