sqrtd32(), sqrtd64(), sqrtd128() — Calculate square root

Standards

Standards / Extensions	C or C++	Dependencies
C/C++ DFP	both	z/OS® V1.8

Format

#define __STDC_WANT_DEC_FP__
#include <math.h>
 
_Decimal32  sqrtd32(_Decimal32 x); 
_Decimal64  sqrtd64(_Decimal64 x);
_Decimal128 sqrtd128(_Decimal128 x);
_Decimal32  sqrt(_Decimal32 x);      /* C++ only */
_Decimal64  sqrt(_Decimal64 x);      /* C++ only */
_Decimal128 sqrt(_Decimal128 x);     /* C++ only */

General description

Calculates the square root of x.

Notes:

To use IEEE decimal floating-point, the hardware must have the Decimal Floating-Point Facility installed.
These functions work in IEEE decimal floating-point format. See "IEEE Decimal Floating-Point" for more information.

Returned value

If successful, returns the square root of x.

If the correct value would cause underflow, zero is returned and the value ERANGE is stored in errno.

If x < -0, the function returns NaNQ and sets errno to EDOM.

If x is a NaN, a NaN will be returned.

If x is ±0 or +INF, x will be returned.

If x is -INF, the function returns NaNQ and sets errno to EDOM.

Example

⁄* CELEBS71

   This example illustrates the sqrtd32() function, along with
   the strtod32() function.

   This example computes the square root of the quantity passed
   as the first argument to main.
   It prints an error message if you pass a negative value.

*⁄

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

int main(int argc, char ** argv)
{
  char        *rest;
  _Decimal32   value;

  if (argc != 2)
  {
    printf("Usage: %s value\n", argv[0]);
  }
  else
  {
    value = strtod32(argv[1], &rest);

    if (value < 0.0DF)
      printf("sqrt of a negative number\n");
    else
      printf("sqrt(%Hf) = %Hf\n", value, sqrtd32(value));
  }
}