func ExampleRoundingMode() {
	operands := []float64{2.6, 2.5, 2.1, -2.1, -2.5, -2.6}

	fmt.Print("   x")
	for mode := big.ToNearestEven; mode <= big.ToPositiveInf; mode++ {
		fmt.Printf("  %s", mode)
	}
	fmt.Println()

	for _, f64 := range operands {
		fmt.Printf("%4g", f64)
		for mode := big.ToNearestEven; mode <= big.ToPositiveInf; mode++ {
			// sample operands above require 2 bits to represent mantissa

		{4, ToNearestEven, '*', "1", "0x.8p2147483647", "0x.8p+2147483647", Exact},
		{4, ToNearestEven, '*', "2", "0x.8p2147483647", "+Inf", Above},  // exponent overflow in *
		{4, ToNearestEven, '*', "-2", "0x.8p2147483647", "-Inf", Below}, // exponent overflow in *

		{4, ToNearestEven, '/', "0.5", "0x.8p2147483647", "0x.8p-2147483646", Exact},
		{4, ToNearestEven, '/', "0x.8p+0", "0x.8p2147483647", "0x.8p-2147483646", Exact},

package big

import "strconv"

func _() {
	// An "invalid array index" compiler error signifies that the constant values have changed.
	// Re-run the stringer command to generate them again.
	var x [1]struct{}
	_ = x[ToNearestEven-0]
	_ = x[ToNearestAway-1]
	_ = x[ToZero-2]
	_ = x[AwayFromZero-3]
	_ = x[ToNegativeInf-4]
	_ = x[ToPositiveInf-5]
}

		{"-8191.53125", ToPositiveInf, 53, 'x', 4, "-0x1.fff8p+12"},

		// issue 34343
		{"0x.8p-2147483648", ToNearestEven, 4, 'p', -1, "0x.8p-2147483648"},
		{"0x.8p-2147483648", ToNearestEven, 4, 'x', -1, "0x1p-2147483649"},
	} {
		f, _, err := ParseFloat(test.x, 0, test.prec, ToNearestEven)
		if err != nil {
			t.Errorf("%v: %s", test, err)
			continue
		}
		if test.round != defaultRound {

	dec := gob.NewDecoder(&medium)
	for _, test := range floatVals {
		for _, sign := range []string{"", "+", "-"} {
			for _, prec := range []uint{0, 1, 2, 10, 53, 64, 100, 1000} {
				for _, mode := range []RoundingMode{ToNearestEven, ToNearestAway, ToZero, AwayFromZero, ToNegativeInf, ToPositiveInf} {
					medium.Reset() // empty buffer for each test case (in case of failures)
					x := sign + test

					var tx Float

			if b == r+1 {
				bit0 = 1
			}
			z = append(z, b)
		}
	}

	// round
	f := z.Float() // rounded to zero
	if mode == ToNearestAway {
		panic("not yet implemented")
	}
	if mode == ToNearestEven && rbit == 1 && (sbit == 1 || sbit == 0 && bit0 != 0) || mode == AwayFromZero {
		// round away from zero
		f.SetMode(ToZero).SetPrec(prec)
		f.Add(f, Bits{int(r) + 1}.Float())
	}
	return f
}

// precision set to a reasonable value determined by the operands, and
// their mode is the zero value for RoundingMode (ToNearestEven).
//
// By setting the desired precision to 24 or 53 and using matching rounding
// mode (typically [ToNearestEven]), Float operations produce the same results
// as the corresponding float32 or float64 IEEE 754 arithmetic for operands

	// 3) Compute upper bound by adding 1/2 ulp.
	var upper decimal
	upper.init(tmp.add(mant, natOne), exp)

	// The upper and lower bounds are possible outputs only if
	// the original mantissa is even, so that ToNearestEven rounding
	// would round to the original mantissa and not the neighbors.
	inclusive := mant[0]&2 == 0 // test bit 1 since original mantissa was shifted by 1

	// Now we can figure out the minimum number of digits required.

pkg math/big, const MinExp = -2147483648
pkg math/big, const MinExp ideal-int
pkg math/big, const ToNearestAway = 1
pkg math/big, const ToNearestAway RoundingMode
pkg math/big, const ToNearestEven = 0
pkg math/big, const ToNearestEven RoundingMode
pkg math/big, const ToNegativeInf = 4
pkg math/big, const ToNegativeInf RoundingMode
pkg math/big, const ToPositiveInf = 5
pkg math/big, const ToPositiveInf RoundingMode

		{"NewFloat", Func, 5},
		{"NewInt", Func, 0},
		{"NewRat", Func, 0},
		{"ParseFloat", Func, 5},
		{"Rat", Type, 0},
		{"RoundingMode", Type, 5},
		{"ToNearestAway", Const, 5},
		{"ToNearestEven", Const, 5},
		{"ToNegativeInf", Const, 5},
		{"ToPositiveInf", Const, 5},
		{"ToZero", Const, 5},
		{"Word", Type, 0},
	},
	"math/bits": {
		{"Add", Func, 12},
		{"Add32", Func, 12},