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Annotation of cci/usr/src/usr.lib/libF77/c_sqrt.c, revision 1.1

1.1     ! root        1: /*
        !             2:  *     "@(#)c_sqrtf.c  1.1"
        !             3:  */
        !             4: 
        !             5: #include "complex"
        !             6: 
        !             7: /* THIS IS BASED ON TAHOE FLOATING POINT REPR. */
        !             8: #include <FP.h>
        !             9: 
        !            10: c_sqrt(r, z)
        !            11: register complex *r, *z;
        !            12: {
        !            13: float mag, cabs();
        !            14: fortran float sqrt();
        !            15: 
        !            16: if( (mag = cabs(z->real, z->imag)) == 0.)
        !            17:        r->real = r->imag = 0.;
        !            18: else if(z->real > 0)
        !            19:        {
        !            20:        r->real = sqrt(0.5 * (mag + z->real) );
        !            21:        r->imag = z->imag / r->real / 2;
        !            22:        }
        !            23: else
        !            24:        {
        !            25:        r->imag = sqrt(0.5 * (mag - z->real) );
        !            26:        if(z->imag < 0)
        !            27:                *(unsigned long*)&(r->imag) ^= SIGN_BIT;
        !            28:        r->real = z->imag / r->imag /2;
        !            29:        }
        !            30: }

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