Merge aa8a681072 into a1bdfc355e

helpers.go

@@ -0,0 +1,38 @@
+package decimal
+
+// Float returns the decimal value as a float64
+// float is a helper function for float64() and doesnot return bool exact
+func (d Decimal) Float() float64 {
+	f, _ := d.Float64()
+	return f
+}
+
+// NotEqual returns true when d is not equal to d2
+func (d Decimal) NotEqual(d2 Decimal) bool {
+	return !d.Equal(d2)
+}
+
+// Max returns the maximum value between d and d2
+func (d Decimal) Max(d2 Decimal) Decimal {
+	return Max(d, d2)
+}
+
+// Min returns the minimum value between d and d2
+func (d Decimal) Min(d2 Decimal) Decimal {
+	return Min(d, d2)
+}
+
+//NewFromInt returns a decimal with the value of int v
+func NewFromInt(v int) Decimal {
+	return New(int64(v), 0)
+}
+
+//NewFromInt32 returns a decimal with the value of int v
+func NewFromInt32(v int) Decimal {
+	return New(int64(v), 0)
+}
+
+//NewFromInt64 returns a decimal with the value of int v
+func NewFromInt64(v int64) Decimal {
+	return New(v, 0)
+}

numbers.go

@@ -0,0 +1,124 @@
+package decimal
+
+// MinusOne defines value -1 in decimal format
+var MinusOne = New(-1, 0)
+
+// OneTenth defines value 0.1 in decimal format
+var OneTenth = New(1, -1)
+
+// TwoTenth defines value 0.1 in decimal format
+var TwoTenth = New(2, -1)
+
+// Half defines value 0.5 in decimal format
+var Half = New(5, -1)
+
+// One defines value 1 in decimal format
+var One = New(1, 0)
+
+// Two defines value 2 in decimal format
+var Two = New(2, 0)
+
+// Three defines value 3 in decimal format
+var Three = New(3, 0)
+
+// Four defines value 4 in decimal format
+var Four = New(4, 0)
+
+// Five defines value 5 in decimal format
+var Five = New(5, 0)
+
+// Six defines value 6 in decimal format
+var Six = New(6, 0)
+
+// Seven defines value 6 in decimal format
+var Seven = New(7, 0)
+
+// Eight defines value 8 in decimal format
+var Eight = New(8, 0)
+
+// Nine defines value 9 in decimal format
+var Nine = New(9, 0)
+
+// Ten defines value 10 in decimal format
+var Ten = New(10, 0)
+
+// Eleven defines value 11 in decimal format
+var Eleven = New(11, 0)
+
+// Twelve defines value 12 in decimal format
+var Twelve = New(12, 0)
+
+// Thirteen defines value 13 in decimal format
+var Thirteen = New(13, 0)
+
+// Fourteen defines value 14 in decimal format
+var Fourteen = New(14, 0)
+
+// Fifteen defines value 15 in decimal format
+var Fifteen = New(15, 0)
+
+// Sixteen defines value 16 in decimal format
+var Sixteen = New(16, 0)
+
+// Seventeen defines value 17 in decimal format
+var Seventeen = New(17, 0)
+
+// Eighteen defines value 18 in decimal format
+var Eighteen = New(18, 0)
+
+// Nineteen defines value 19 in decimal format
+var Nineteen = New(19, 0)
+
+// Twenty defines value 20 in decimal format
+var Twenty = New(20, 0)
+
+// Thirty defines value 30 in decimal format
+var Thirty = New(30, 0)
+
+// Forty defines value 40 in decimal format
+var Forty = New(40, 0)
+
+// Fifty defines value 50 in decimal format
+var Fifty = New(50, 0)
+
+// Sixty defines value 60 in decimal format
+var Sixty = New(60, 0)
+
+// Seventy defines value 70 in decimal format
+var Seventy = New(70, 0)
+
+// Eighty defines value 80 in decimal format
+var Eighty = New(80, 0)
+
+// Ninty defines value 90 in decimal format
+var Ninty = New(90, 0)
+
+// Hundred defines value 100 in decimal format
+var Hundred = New(100, 0)
+
+// TwoHundred defines value 200 in decimal format
+var TwoHundred = New(200, 0)
+
+// ThreeHundred defines value 300 in decimal format
+var ThreeHundred = New(300, 0)
+
+// FourHundred defines value 400 in decimal format
+var FourHundred = New(400, 0)
+
+// FiveHundred defines value 500 in decimal format
+var FiveHundred = New(500, 0)
+
+// SixHundred defines value 600 in decimal format
+var SixHundred = New(600, 0)
+
+// SevenHundred defines value 700 in decimal format
+var SevenHundred = New(700, 0)
+
+// EightHundred defines value 800 in decimal format
+var EightHundred = New(800, 0)
+
+// NineHundred defines value 900 in decimal format
+var NineHundred = New(900, 0)
+
+// Thousand defines value 100 in decimal format
+var Thousand = New(1000, 0)

sqrt.go

@@ -0,0 +1,35 @@
+package decimal
+
+const sqrtMaxIter = 10000
+
+// Sqrt returns the square root of d, the result will have
+// DivisionPrecision digits after the decimal point.
+func (d Decimal) Sqrt() Decimal {
+	s, _ := d.SqrtRound(int32(DivisionPrecision))
+	return s
+}
+
+// SqrtRound returns the square root of d, the result will have
+// precision digits after the decimal point. The bool precise returns whether the precision was reached
+func (d Decimal) SqrtRound(precision int32) (Decimal, bool) {
+	if d.LessThanOrEqualZero() {
+		return Zero, false
+	}
+	cutoff := New(1, -precision)
+	lo := Zero
+	hi := d
+	var mid Decimal
+	for i := 0; i < sqrtMaxIter; i++ {
+		//mid = (lo+hi)/2;
+		mid = lo.Add(hi).DivRound(Two, precision)
+		if mid.Mul(mid).Sub(d).Abs().LessThan(cutoff) {
+			return mid, true
+		}
+		if mid.Mul(mid).GreaterThan(d) {
+			hi = mid
+		} else {
+			lo = mid
+		}
+	}
+	return mid, false
+}

sqrt_test.go

@@ -0,0 +1,24 @@
+package decimal
+
+import (
+	"testing"
+)
+
+func TestSqrt(t *testing.T) {
+	tables := []struct {
+		x Decimal
+		n Decimal
+	}{
+		{One, One},
+		{Four, Two},
+		{Sixteen, Four},
+		{Two, NewFromFloat(1.4142135623730951)},
+	}
+
+	for _, table := range tables {
+		result := table.x.Sqrt()
+		if result.NotEqual(table.n) {
+			t.Errorf("Sqrt of (%v) was incorrect, got: %v, want: %v.", table.x.String(), result.String(), table.n.String())
+		}
+	}
+}

zero.go

@@ -0,0 +1,31 @@
+package decimal
+
+// EqualZero returns whether the numbers represented by d equals zero.
+func (d Decimal) EqualZero() bool {
+	return d.Equal(Zero)
+}
+
+// NotZero returns whether d is not zero
+func (d Decimal) NotZero() bool {
+	return !d.EqualZero()
+}
+
+// GreaterThanZero (GT0) returns true when d is greater than zero.
+func (d Decimal) GreaterThanZero() bool {
+	return d.GreaterThan(Zero)
+}
+
+// GreaterThanOrEqualZero (GTE0) returns true when d is greater than or equal to zero.
+func (d Decimal) GreaterThanOrEqualZero() bool {
+	return d.GreaterThanOrEqual(Zero)
+}
+
+// LessThanZero returns true when d is less than zero.
+func (d Decimal) LessThanZero() bool {
+	return d.LessThan(Zero)
+}
+
+// LessThanOrEqualZero returns true when d is less than or equal to zero.
+func (d Decimal) LessThanOrEqualZero() bool {
+	return d.LessThanOrEqual(Zero)
+}