_WMRTLINK extended _IF_PowXI( extended base, intstar4 power ) {
//============================================================
// Return base ** power where power could be <= 0.
extended result;
if( base == 0.0 ) {
if( power <= 0 ) {
result = power;
return( __math2err( FUNC_DPOWI | M_DOMAIN | V_ZERO, &base, &result ) );
} else {
return( 0.0 );
}
} else {
if( power < 0 ) {
power = -power;
base = PDIV( 1.0 , base );
}
result = 1.0;
while( power > 0 ) {
if( power % 2 == 0 ) {
base *= base;
power /= 2;
} else {
result *= base;
--power;
}
}
return( result );
}
}
double PowRI( double base, intstar4 power ) {
//============================================
// Return base ** power where power could be <= 0.
double result;
if( base == 0.0 ) {
if( power <= 0 ) {
result = power;
return( __math2err( FUNC_DPOWI | M_DOMAIN | V_ZERO, &base, &result ) );
} else {
return( 0.0 );
}
} else {
if( power < 0 ) {
power = -power;
base = 1 / base;
}
result = 1.0;
while( power > 0 ) {
if( power % 2 == 0 ) {
base *= base;
power /= 2;
} else {
result *= base;
--power;
}
}
return( result );
}
}
_WMRTLINK double _IF_datan2( double y, double x )
/***********************************************/
{
int sgnx; /* sgn(x) */
int sgny; /* sgn(y) */
int sgnz; /* sgn(z) */
sgny = __sgn( y );
sgnx = __sgn( x );
if( sgny == 0 ) { /* case 1 */
if( sgnx == 0 ) {
x = __math2err( FUNC_ATAN2 | M_DOMAIN | V_ZERO, &y, &x );
} else if( sgnx < 0 ) {
x = Pi;
} else {
x = 0.0;
}
} else if( sgnx == 0 ) { /* case 2 */
if( sgny < 0 ) {
x = -Piby2;
} else {
x = Piby2;
}
} else {
int exp_x;
int exp_y;
int diff_exp_y_x;
frexp( y, &exp_y );
frexp( x, &exp_x );
diff_exp_y_x = exp_y - exp_x;
if( diff_exp_y_x > DBL_MAX_EXP ) {
if( sgnx == sgny ) {
x = +DBL_MAX;
} else {
x = -DBL_MAX;
}
} else if( diff_exp_y_x < DBL_MIN_EXP ) {
if( sgnx == sgny ) {
x = +DBL_MIN;
} else {
x = -DBL_MIN;
}
} else {
x = PDIV( y, x );
}
x = atan( x );
sgnz = __sgn( x );
if( sgny >= 0 ) {
if( sgnz < 0 ) {
x += Pi;
}
} else {
if( sgnz > 0 ) {
x -= Pi;
}
}
}
return( x );
}
double __math1err( unsigned int err_info, double *a1 ) {
//=======================================================
return( __math2err( err_info, a1, a1 ) );
}
