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-rw-r--r--vendor/github.com/shopspring/decimal/decimal.go473
1 files changed, 450 insertions, 23 deletions
diff --git a/vendor/github.com/shopspring/decimal/decimal.go b/vendor/github.com/shopspring/decimal/decimal.go
index 801c1a045..84405ec1c 100644
--- a/vendor/github.com/shopspring/decimal/decimal.go
+++ b/vendor/github.com/shopspring/decimal/decimal.go
@@ -22,6 +22,7 @@ import (
"fmt"
"math"
"math/big"
+ "regexp"
"strconv"
"strings"
)
@@ -51,6 +52,10 @@ var DivisionPrecision = 16
// silently lose precision.
var MarshalJSONWithoutQuotes = false
+// ExpMaxIterations specifies the maximum number of iterations needed to calculate
+// precise natural exponent value using ExpHullAbrham method.
+var ExpMaxIterations = 1000
+
// Zero constant, to make computations faster.
// Zero should never be compared with == or != directly, please use decimal.Equal or decimal.Cmp instead.
var Zero = New(0, 1)
@@ -63,6 +68,8 @@ var fiveInt = big.NewInt(5)
var tenInt = big.NewInt(10)
var twentyInt = big.NewInt(20)
+var factorials = []Decimal{New(1, 0)}
+
// Decimal represents a fixed-point decimal. It is immutable.
// number = value * 10 ^ exp
type Decimal struct {
@@ -113,7 +120,7 @@ func NewFromInt32(value int32) Decimal {
// NewFromBigInt returns a new Decimal from a big.Int, value * 10 ^ exp
func NewFromBigInt(value *big.Int, exp int32) Decimal {
return Decimal{
- value: big.NewInt(0).Set(value),
+ value: new(big.Int).Set(value),
exp: exp,
}
}
@@ -146,23 +153,45 @@ func NewFromString(value string) (Decimal, error) {
exp = expInt
}
- parts := strings.Split(value, ".")
- if len(parts) == 1 {
+ pIndex := -1
+ vLen := len(value)
+ for i := 0; i < vLen; i++ {
+ if value[i] == '.' {
+ if pIndex > -1 {
+ return Decimal{}, fmt.Errorf("can't convert %s to decimal: too many .s", value)
+ }
+ pIndex = i
+ }
+ }
+
+ if pIndex == -1 {
// There is no decimal point, we can just parse the original string as
// an int
intString = value
- } else if len(parts) == 2 {
- intString = parts[0] + parts[1]
- expInt := -len(parts[1])
- exp += int64(expInt)
} else {
- return Decimal{}, fmt.Errorf("can't convert %s to decimal: too many .s", value)
+ if pIndex+1 < vLen {
+ intString = value[:pIndex] + value[pIndex+1:]
+ } else {
+ intString = value[:pIndex]
+ }
+ expInt := -len(value[pIndex+1:])
+ exp += int64(expInt)
}
- dValue := new(big.Int)
- _, ok := dValue.SetString(intString, 10)
- if !ok {
- return Decimal{}, fmt.Errorf("can't convert %s to decimal", value)
+ var dValue *big.Int
+ // strconv.ParseInt is faster than new(big.Int).SetString so this is just a shortcut for strings we know won't overflow
+ if len(intString) <= 18 {
+ parsed64, err := strconv.ParseInt(intString, 10, 64)
+ if err != nil {
+ return Decimal{}, fmt.Errorf("can't convert %s to decimal", value)
+ }
+ dValue = big.NewInt(parsed64)
+ } else {
+ dValue = new(big.Int)
+ _, ok := dValue.SetString(intString, 10)
+ if !ok {
+ return Decimal{}, fmt.Errorf("can't convert %s to decimal", value)
+ }
}
if exp < math.MinInt32 || exp > math.MaxInt32 {
@@ -176,6 +205,30 @@ func NewFromString(value string) (Decimal, error) {
}, nil
}
+// NewFromFormattedString returns a new Decimal from a formatted string representation.
+// The second argument - replRegexp, is a regular expression that is used to find characters that should be
+// removed from given decimal string representation. All matched characters will be replaced with an empty string.
+//
+// Example:
+//
+// r := regexp.MustCompile("[$,]")
+// d1, err := NewFromFormattedString("$5,125.99", r)
+//
+// r2 := regexp.MustCompile("[_]")
+// d2, err := NewFromFormattedString("1_000_000", r2)
+//
+// r3 := regexp.MustCompile("[USD\\s]")
+// d3, err := NewFromFormattedString("5000 USD", r3)
+//
+func NewFromFormattedString(value string, replRegexp *regexp.Regexp) (Decimal, error) {
+ parsedValue := replRegexp.ReplaceAllString(value, "")
+ d, err := NewFromString(parsedValue)
+ if err != nil {
+ return Decimal{}, err
+ }
+ return d, nil
+}
+
// RequireFromString returns a new Decimal from a string representation
// or panics if NewFromString would have returned an error.
//
@@ -361,6 +414,15 @@ func NewFromFloatWithExponent(value float64, exp int32) Decimal {
}
}
+// Copy returns a copy of decimal with the same value and exponent, but a different pointer to value.
+func (d Decimal) Copy() Decimal {
+ d.ensureInitialized()
+ return Decimal{
+ value: &(*d.value),
+ exp: d.exp,
+ }
+}
+
// rescale returns a rescaled version of the decimal. Returned
// decimal may be less precise if the given exponent is bigger
// than the initial exponent of the Decimal.
@@ -410,6 +472,9 @@ func (d Decimal) rescale(exp int32) Decimal {
// Abs returns the absolute value of the decimal.
func (d Decimal) Abs() Decimal {
+ if !d.IsNegative() {
+ return d
+ }
d.ensureInitialized()
d2Value := new(big.Int).Abs(d.value)
return Decimal{
@@ -583,6 +648,207 @@ func (d Decimal) Pow(d2 Decimal) Decimal {
return temp.Mul(temp).Div(d)
}
+// ExpHullAbrham calculates the natural exponent of decimal (e to the power of d) using Hull-Abraham algorithm.
+// OverallPrecision argument specifies the overall precision of the result (integer part + decimal part).
+//
+// ExpHullAbrham is faster than ExpTaylor for small precision values, but it is much slower for large precision values.
+//
+// Example:
+//
+// NewFromFloat(26.1).ExpHullAbrham(2).String() // output: "220000000000"
+// NewFromFloat(26.1).ExpHullAbrham(20).String() // output: "216314672147.05767284"
+//
+func (d Decimal) ExpHullAbrham(overallPrecision uint32) (Decimal, error) {
+ // Algorithm based on Variable precision exponential function.
+ // ACM Transactions on Mathematical Software by T. E. Hull & A. Abrham.
+ if d.IsZero() {
+ return Decimal{oneInt, 0}, nil
+ }
+
+ currentPrecision := overallPrecision
+
+ // Algorithm does not work if currentPrecision * 23 < |x|.
+ // Precision is automatically increased in such cases, so the value can be calculated precisely.
+ // If newly calculated precision is higher than ExpMaxIterations the currentPrecision will not be changed.
+ f := d.Abs().InexactFloat64()
+ if ncp := f / 23; ncp > float64(currentPrecision) && ncp < float64(ExpMaxIterations) {
+ currentPrecision = uint32(math.Ceil(ncp))
+ }
+
+ // fail if abs(d) beyond an over/underflow threshold
+ overflowThreshold := New(23*int64(currentPrecision), 0)
+ if d.Abs().Cmp(overflowThreshold) > 0 {
+ return Decimal{}, fmt.Errorf("over/underflow threshold, exp(x) cannot be calculated precisely")
+ }
+
+ // Return 1 if abs(d) small enough; this also avoids later over/underflow
+ overflowThreshold2 := New(9, -int32(currentPrecision)-1)
+ if d.Abs().Cmp(overflowThreshold2) <= 0 {
+ return Decimal{oneInt, d.exp}, nil
+ }
+
+ // t is the smallest integer >= 0 such that the corresponding abs(d/k) < 1
+ t := d.exp + int32(d.NumDigits()) // Add d.NumDigits because the paper assumes that d.value [0.1, 1)
+
+ if t < 0 {
+ t = 0
+ }
+
+ k := New(1, t) // reduction factor
+ r := Decimal{new(big.Int).Set(d.value), d.exp - t} // reduced argument
+ p := int32(currentPrecision) + t + 2 // precision for calculating the sum
+
+ // Determine n, the number of therms for calculating sum
+ // use first Newton step (1.435p - 1.182) / log10(p/abs(r))
+ // for solving appropriate equation, along with directed
+ // roundings and simple rational bound for log10(p/abs(r))
+ rf := r.Abs().InexactFloat64()
+ pf := float64(p)
+ nf := math.Ceil((1.453*pf - 1.182) / math.Log10(pf/rf))
+ if nf > float64(ExpMaxIterations) || math.IsNaN(nf) {
+ return Decimal{}, fmt.Errorf("exact value cannot be calculated in <=ExpMaxIterations iterations")
+ }
+ n := int64(nf)
+
+ tmp := New(0, 0)
+ sum := New(1, 0)
+ one := New(1, 0)
+ for i := n - 1; i > 0; i-- {
+ tmp.value.SetInt64(i)
+ sum = sum.Mul(r.DivRound(tmp, p))
+ sum = sum.Add(one)
+ }
+
+ ki := k.IntPart()
+ res := New(1, 0)
+ for i := ki; i > 0; i-- {
+ res = res.Mul(sum)
+ }
+
+ resNumDigits := int32(res.NumDigits())
+
+ var roundDigits int32
+ if resNumDigits > abs(res.exp) {
+ roundDigits = int32(currentPrecision) - resNumDigits - res.exp
+ } else {
+ roundDigits = int32(currentPrecision)
+ }
+
+ res = res.Round(roundDigits)
+
+ return res, nil
+}
+
+// ExpTaylor calculates the natural exponent of decimal (e to the power of d) using Taylor series expansion.
+// Precision argument specifies how precise the result must be (number of digits after decimal point).
+// Negative precision is allowed.
+//
+// ExpTaylor is much faster for large precision values than ExpHullAbrham.
+//
+// Example:
+//
+// d, err := NewFromFloat(26.1).ExpTaylor(2).String()
+// d.String() // output: "216314672147.06"
+//
+// NewFromFloat(26.1).ExpTaylor(20).String()
+// d.String() // output: "216314672147.05767284062928674083"
+//
+// NewFromFloat(26.1).ExpTaylor(-10).String()
+// d.String() // output: "220000000000"
+//
+func (d Decimal) ExpTaylor(precision int32) (Decimal, error) {
+ // Note(mwoss): Implementation can be optimized by exclusively using big.Int API only
+ if d.IsZero() {
+ return Decimal{oneInt, 0}.Round(precision), nil
+ }
+
+ var epsilon Decimal
+ var divPrecision int32
+ if precision < 0 {
+ epsilon = New(1, -1)
+ divPrecision = 8
+ } else {
+ epsilon = New(1, -precision-1)
+ divPrecision = precision + 1
+ }
+
+ decAbs := d.Abs()
+ pow := d.Abs()
+ factorial := New(1, 0)
+
+ result := New(1, 0)
+
+ for i := int64(1); ; {
+ step := pow.DivRound(factorial, divPrecision)
+ result = result.Add(step)
+
+ // Stop Taylor series when current step is smaller than epsilon
+ if step.Cmp(epsilon) < 0 {
+ break
+ }
+
+ pow = pow.Mul(decAbs)
+
+ i++
+
+ // Calculate next factorial number or retrieve cached value
+ if len(factorials) >= int(i) && !factorials[i-1].IsZero() {
+ factorial = factorials[i-1]
+ } else {
+ // To avoid any race conditions, firstly the zero value is appended to a slice to create
+ // a spot for newly calculated factorial. After that, the zero value is replaced by calculated
+ // factorial using the index notation.
+ factorial = factorials[i-2].Mul(New(i, 0))
+ factorials = append(factorials, Zero)
+ factorials[i-1] = factorial
+ }
+ }
+
+ if d.Sign() < 0 {
+ result = New(1, 0).DivRound(result, precision+1)
+ }
+
+ result = result.Round(precision)
+ return result, nil
+}
+
+// NumDigits returns the number of digits of the decimal coefficient (d.Value)
+// Note: Current implementation is extremely slow for large decimals and/or decimals with large fractional part
+func (d Decimal) NumDigits() int {
+ // Note(mwoss): It can be optimized, unnecessary cast of big.Int to string
+ if d.IsNegative() {
+ return len(d.value.String()) - 1
+ }
+ return len(d.value.String())
+}
+
+// IsInteger returns true when decimal can be represented as an integer value, otherwise, it returns false.
+func (d Decimal) IsInteger() bool {
+ // The most typical case, all decimal with exponent higher or equal 0 can be represented as integer
+ if d.exp >= 0 {
+ return true
+ }
+ // When the exponent is negative we have to check every number after the decimal place
+ // If all of them are zeroes, we are sure that given decimal can be represented as an integer
+ var r big.Int
+ q := new(big.Int).Set(d.value)
+ for z := abs(d.exp); z > 0; z-- {
+ q.QuoRem(q, tenInt, &r)
+ if r.Cmp(zeroInt) != 0 {
+ return false
+ }
+ }
+ return true
+}
+
+// Abs calculates absolute value of any int32. Used for calculating absolute value of decimal's exponent.
+func abs(n int32) int32 {
+ if n < 0 {
+ return -n
+ }
+ return n
+}
+
// Cmp compares the numbers represented by d and d2 and returns:
//
// -1 if d < d2
@@ -679,12 +945,18 @@ func (d Decimal) Exponent() int32 {
return d.exp
}
-// Coefficient returns the coefficient of the decimal. It is scaled by 10^Exponent()
+// Coefficient returns the coefficient of the decimal. It is scaled by 10^Exponent()
func (d Decimal) Coefficient() *big.Int {
d.ensureInitialized()
- // we copy the coefficient so that mutating the result does not mutate the
- // Decimal.
- return big.NewInt(0).Set(d.value)
+ // we copy the coefficient so that mutating the result does not mutate the Decimal.
+ return new(big.Int).Set(d.value)
+}
+
+// CoefficientInt64 returns the coefficient of the decimal as int64. It is scaled by 10^Exponent()
+// If coefficient cannot be represented in an int64, the result will be undefined.
+func (d Decimal) CoefficientInt64() int64 {
+ d.ensureInitialized()
+ return d.value.Int64()
}
// IntPart returns the integer component of the decimal.
@@ -730,6 +1002,13 @@ func (d Decimal) Float64() (f float64, exact bool) {
return d.Rat().Float64()
}
+// InexactFloat64 returns the nearest float64 value for d.
+// It doesn't indicate if the returned value represents d exactly.
+func (d Decimal) InexactFloat64() float64 {
+ f, _ := d.Float64()
+ return f
+}
+
// String returns the string representation of the decimal
// with the fixed point.
//
@@ -798,6 +1077,9 @@ func (d Decimal) StringFixedCash(interval uint8) string {
// NewFromFloat(545).Round(-1).String() // output: "550"
//
func (d Decimal) Round(places int32) Decimal {
+ if d.exp == -places {
+ return d
+ }
// truncate to places + 1
ret := d.rescale(-places - 1)
@@ -818,6 +1100,107 @@ func (d Decimal) Round(places int32) Decimal {
return ret
}
+// RoundCeil rounds the decimal towards +infinity.
+//
+// Example:
+//
+// NewFromFloat(545).RoundCeil(-2).String() // output: "600"
+// NewFromFloat(500).RoundCeil(-2).String() // output: "500"
+// NewFromFloat(1.1001).RoundCeil(2).String() // output: "1.11"
+// NewFromFloat(-1.454).RoundCeil(1).String() // output: "-1.5"
+//
+func (d Decimal) RoundCeil(places int32) Decimal {
+ if d.exp >= -places {
+ return d
+ }
+
+ rescaled := d.rescale(-places)
+ if d.Equal(rescaled) {
+ return d
+ }
+
+ if d.value.Sign() > 0 {
+ rescaled.value.Add(rescaled.value, oneInt)
+ }
+
+ return rescaled
+}
+
+// RoundFloor rounds the decimal towards -infinity.
+//
+// Example:
+//
+// NewFromFloat(545).RoundFloor(-2).String() // output: "500"
+// NewFromFloat(-500).RoundFloor(-2).String() // output: "-500"
+// NewFromFloat(1.1001).RoundFloor(2).String() // output: "1.1"
+// NewFromFloat(-1.454).RoundFloor(1).String() // output: "-1.4"
+//
+func (d Decimal) RoundFloor(places int32) Decimal {
+ if d.exp >= -places {
+ return d
+ }
+
+ rescaled := d.rescale(-places)
+ if d.Equal(rescaled) {
+ return d
+ }
+
+ if d.value.Sign() < 0 {
+ rescaled.value.Sub(rescaled.value, oneInt)
+ }
+
+ return rescaled
+}
+
+// RoundUp rounds the decimal away from zero.
+//
+// Example:
+//
+// NewFromFloat(545).RoundUp(-2).String() // output: "600"
+// NewFromFloat(500).RoundUp(-2).String() // output: "500"
+// NewFromFloat(1.1001).RoundUp(2).String() // output: "1.11"
+// NewFromFloat(-1.454).RoundUp(1).String() // output: "-1.4"
+//
+func (d Decimal) RoundUp(places int32) Decimal {
+ if d.exp >= -places {
+ return d
+ }
+
+ rescaled := d.rescale(-places)
+ if d.Equal(rescaled) {
+ return d
+ }
+
+ if d.value.Sign() > 0 {
+ rescaled.value.Add(rescaled.value, oneInt)
+ } else if d.value.Sign() < 0 {
+ rescaled.value.Sub(rescaled.value, oneInt)
+ }
+
+ return rescaled
+}
+
+// RoundDown rounds the decimal towards zero.
+//
+// Example:
+//
+// NewFromFloat(545).RoundDown(-2).String() // output: "500"
+// NewFromFloat(-500).RoundDown(-2).String() // output: "-500"
+// NewFromFloat(1.1001).RoundDown(2).String() // output: "1.1"
+// NewFromFloat(-1.454).RoundDown(1).String() // output: "-1.5"
+//
+func (d Decimal) RoundDown(places int32) Decimal {
+ if d.exp >= -places {
+ return d
+ }
+
+ rescaled := d.rescale(-places)
+ if d.Equal(rescaled) {
+ return d
+ }
+ return rescaled
+}
+
// RoundBank rounds the decimal to places decimal places.
// If the final digit to round is equidistant from the nearest two integers the
// rounded value is taken as the even number
@@ -826,12 +1209,12 @@ func (d Decimal) Round(places int32) Decimal {
//
// Examples:
//
-// NewFromFloat(5.45).Round(1).String() // output: "5.4"
-// NewFromFloat(545).Round(-1).String() // output: "540"
-// NewFromFloat(5.46).Round(1).String() // output: "5.5"
-// NewFromFloat(546).Round(-1).String() // output: "550"
-// NewFromFloat(5.55).Round(1).String() // output: "5.6"
-// NewFromFloat(555).Round(-1).String() // output: "560"
+// NewFromFloat(5.45).RoundBank(1).String() // output: "5.4"
+// NewFromFloat(545).RoundBank(-1).String() // output: "540"
+// NewFromFloat(5.46).RoundBank(1).String() // output: "5.5"
+// NewFromFloat(546).RoundBank(-1).String() // output: "550"
+// NewFromFloat(5.55).RoundBank(1).String() // output: "5.6"
+// NewFromFloat(555).RoundBank(-1).String() // output: "560"
//
func (d Decimal) RoundBank(places int32) Decimal {
@@ -970,12 +1353,22 @@ func (d Decimal) MarshalJSON() ([]byte, error) {
// UnmarshalBinary implements the encoding.BinaryUnmarshaler interface. As a string representation
// is already used when encoding to text, this method stores that string as []byte
func (d *Decimal) UnmarshalBinary(data []byte) error {
+ // Verify we have at least 4 bytes for the exponent. The GOB encoded value
+ // may be empty.
+ if len(data) < 4 {
+ return fmt.Errorf("error decoding binary %v: expected at least 4 bytes, got %d", data, len(data))
+ }
+
// Extract the exponent
d.exp = int32(binary.BigEndian.Uint32(data[:4]))
// Extract the value
d.value = new(big.Int)
- return d.value.GobDecode(data[4:])
+ if err := d.value.GobDecode(data[4:]); err != nil {
+ return fmt.Errorf("error decoding binary %v: %s", data, err)
+ }
+
+ return nil
}
// MarshalBinary implements the encoding.BinaryMarshaler interface.
@@ -1219,6 +1612,13 @@ type NullDecimal struct {
Valid bool
}
+func NewNullDecimal(d Decimal) NullDecimal {
+ return NullDecimal{
+ Decimal: d,
+ Valid: true,
+ }
+}
+
// Scan implements the sql.Scanner interface for database deserialization.
func (d *NullDecimal) Scan(value interface{}) error {
if value == nil {
@@ -1255,6 +1655,33 @@ func (d NullDecimal) MarshalJSON() ([]byte, error) {
return d.Decimal.MarshalJSON()
}
+// UnmarshalText implements the encoding.TextUnmarshaler interface for XML
+// deserialization
+func (d *NullDecimal) UnmarshalText(text []byte) error {
+ str := string(text)
+
+ // check for empty XML or XML without body e.g., <tag></tag>
+ if str == "" {
+ d.Valid = false
+ return nil
+ }
+ if err := d.Decimal.UnmarshalText(text); err != nil {
+ d.Valid = false
+ return err
+ }
+ d.Valid = true
+ return nil
+}
+
+// MarshalText implements the encoding.TextMarshaler interface for XML
+// serialization.
+func (d NullDecimal) MarshalText() (text []byte, err error) {
+ if !d.Valid {
+ return []byte{}, nil
+ }
+ return d.Decimal.MarshalText()
+}
+
// Trig functions
// Atan returns the arctangent, in radians, of x.
generated by cgit v1.2.3 (git 2.46.0) at 2025-07-13 18:43:01 +0000