if x < 0.25 {
		return -Sin(Pi * x)
	}

	// argument reduction
	z := Floor(x)
	var n int
	if z != x { // inexact
		x = Mod(x, 2)
		n = int(x * 4)
	} else {
		if x >= Two53 { // x must be even
			x = 0
			n = 0
		} else {
			if x < Two52 {
				z = x + Two52 // exact
			}
			n = int(1 & Float64bits(z))
			x = float64(n)
			n <<= 2
		}
	}
	switch n {
	case 0:

//              |R1/S1 - f(x)|  < 2**(-62.57)
//              |R2/S2 - f(x)|  < 2**(-61.52)
//
//      5. For inf > x >= 28
//              erf(x)  = sign(x) *(1 - tiny)  (raise inexact)
//              erfc(x) = tiny*tiny (raise underflow) if x > 0
//                      = 2 - tiny if x<0
//
//      7. Special case:
//              erf(0)  = 0, erf(inf)  = 1, erf(-inf) = -1,

		} else {
			u := pone(x)
			v := qone(x)
			z = (1 / SqrtPi) * (u*cc - v*ss) / Sqrt(x)
		}
		if sign {
			return -z
		}
		return z
	}
	if x < TwoM27 { // |x|<2**-27
		return 0.5 * x // inexact if x!=0 necessary
	}
	z := x * x
	r := z * (R00 + z*(R01+z*(R02+z*R03)))
	s := 1.0 + z*(S01+z*(S02+z*(S03+z*(S04+z*S05))))
	r *= x
	z = 0.5*x + r/s
	if sign {
		return -z
	}
	return z
}

// entirely in floating-point math, do so, avoiding the expense of decimalToFloatBits.
// Three common cases:
//
//	value is exact integer
//	value is exact integer * exact power of ten
//	value is exact integer / exact power of ten
//
// These all produce potentially inexact but correctly rounded answers.
func atof64exact(mantissa uint64, exp int, neg bool) (f float64, ok bool) {
	if mantissa>>float64info.mantbits != 0 {

func (q *Quantity) RoundUp(scale Scale) bool {
	if q.d.Dec != nil {
		q.s = ""
		d, exact := q.d.AsScale(scale)
		q.d = d
		return exact
	}
	// avoid clearing the string value if we have already calculated it
	if q.i.scale >= scale {
		return true
	}
	q.s = ""
	i, exact := q.i.AsScale(scale)
	q.i = i
	return exact
}

// Add adds the provide y quantity to the current value. If the current value is zero,

		[6]*argField{ap_ImmUnsigned_15_15, ap_VecReg_6_10, ap_VecReg_16_20, ap_ImmUnsigned_21_22}},
	{XSRQPIX, 0xfc0001ff00000000, 0xfc00000b00000000, 0x1e000000000000, // VSX Scalar Round to Quad-Precision Integer [with Inexact] Z23-form (xsrqpix R,VRT,VRB,RMC)

		if x.neg {
			var z float64
			return -z, Exact
		}
		return 0.0, Exact

	case inf:
		if x.neg {
			return math.Inf(-1), Exact
		}
		return math.Inf(+1), Exact
	}

	panic("unreachable")
}

// Int returns the result of truncating x towards zero;
// or nil if x is an infinity.
// The result is [Exact] if x.IsInt(); otherwise it is [Below]

//
// Before wildcards were introduced, it was clear that an exact match meant
// that the pattern and path were the same string. The only other possibility
// was that a trailing-slash pattern, like "/", matched a path longer than
// it, like "/a".
//
// With wildcards, we define an inexact match as any one where a multi wildcard
// matches a non-empty string. All other matches are exact.
// For example, these are all exact matches:
//

    ```

...then because `description` has a default value, if you **don't return anything** for that field, it will still have that **default value**.

### Model for Output Response Data

If you interact with the docs and check the response, even though the code didn't add anything in one of the `description` fields, the JSON response contains the default value (`null`):

<div class="screenshot">

        return true;
    }

    @Override
    public boolean accept(String candidate) {
        return version.isEmpty() || version.equals(candidate);
    }

    public static boolean isExact(String selector) {
        return selector != null && !VersionRangeSelector.ALL_RANGE.matcher(selector).matches() && !selector.endsWith("+") && !selector.startsWith("latest.");
    }