asin.c File Reference

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Macros
#define	PRECISION   9

Functions
double	asin (double x)

Macro Definition Documentation

PRECISION

#define PRECISION   9

Definition at line 9 of file asin.c.

Function Documentation

asin()

double asin

(

double

x

)

Definition at line 31 of file asin.c.

{
    double x2, result;
 
    /* Check range */
    if ((x > 1.) || (x < -1.)) return NaN;
 
    /* Calculate the square of x */
    x2 = (x * x);
 
    /* Start with 0, compiler will optimize this away */
    result = 0;
 
    result += (15*13*11*9*7*5*3*1./(16*14*12*10*8*6*4*2*17));
    result *= x2;
 
    result += (13*11*9*7*5*3*1./(14*12*10*8*6*4*2*15));
    result *= x2;
 
    result += (11*9*7*5*3*1./(12*10*8*6*4*2*13));
    result *= x2;
 
    result += (9*7*5*3*1./(10*8*6*4*2*11));
    result *= x2;
 
    result += (7*5*3*1./(8*6*4*2*9));
    result *= x2;
 
    result += (5*3*1./(6*4*2*7));
    result *= x2;
 
    result += (3*1./(4*2*5));
    result *= x2;
 
    result += (1./(2*3));
    result *= x2;
 
    result += 1.;
    result *= x;
 
    return result;
}