4.3BSD-UWisc/man/cat3/sqrt.3m




SQRT(3M)            UNIX Programmer's Manual             SQRT(3M)



NAME
     cbrt, sqrt - cube root, square root

SYNOPSIS
     #include <math.h>

     double cbrt(x)
     double x;

     double sqrt(x)
     double x;

DESCRIPTION
     Cbrt(x) returns the cube root of x.

     Sqrt(x) returns the square root of x.

DIAGNOSTICS
     On a VAX, sqrt(negative) returns the reserved operand and
     sets _e_r_r_n_o to EDOM .

ERROR (due to Roundoff etc.)
     Cbrt is accurate to within 0.7 _u_l_ps.
     Sqrt on a VAX is accurate to within 0.501 _u_l_ps.
     Sqrt on a machine that conforms to IEEE 754 is correctly
     rounded in accordance with the rounding mode in force; the
     error is less than half an _u_l_p in the default mode
     (round-to-nearest).  An _u_l_p is one _Unit in the _Last _Place
     carried.

SEE ALSO
     math(3M), infnan(3M)

AUTHOR
     W. Kahan




















Printed 12/27/86          May 12, 1986                          1