**(p1)
public
Raises fix to the numeric power, which may be negative or fractional.
2 ** 3
2 ** -1
2 ** 0.5
Show source
static VALUE
fix_pow(VALUE x, VALUE y)
{
long a = FIX2LONG(x);
if (FIXNUM_P(y)) {
long b = FIX2LONG(y);
if (b < 0)
return rb_funcall(rb_rational_raw1(x), rb_intern("**"), 1, y);
if (b == 0) return INT2FIX(1);
if (b == 1) return x;
if (a == 0) {
if (b > 0) return INT2FIX(0);
return DBL2NUM(INFINITY);
}
if (a == 1) return INT2FIX(1);
if (a == -1) {
if (b % 2 == 0)
return INT2FIX(1);
else
return INT2FIX(-1);
}
return int_pow(a, b);
}
switch (TYPE(y)) {
case T_BIGNUM:
if (rb_funcall(y, '<', 1, INT2FIX(0)))
return rb_funcall(rb_rational_raw1(x), rb_intern("**"), 1, y);
if (a == 0) return INT2FIX(0);
if (a == 1) return INT2FIX(1);
if (a == -1) {
if (int_even_p(y)) return INT2FIX(1);
else return INT2FIX(-1);
}
x = rb_int2big(FIX2LONG(x));
return rb_big_pow(x, y);
case T_FLOAT:
if (RFLOAT_VALUE(y) == 0.0) return DBL2NUM(1.0);
if (a == 0) {
return DBL2NUM(RFLOAT_VALUE(y) < 0 ? INFINITY : 0.0);
}
if (a == 1) return DBL2NUM(1.0);
{
double dy = RFLOAT_VALUE(y);
if (a < 0 && dy != round(dy))
return rb_funcall(rb_complex_raw1(x), rb_intern("**"), 1, y);
return DBL2NUM(pow((double)a, dy));
}
default:
return rb_num_coerce_bin(x, y, rb_intern("**"));
}
}