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Add functions to support precise float compute of weight (#5663)

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This commit is contained in:
mikezhang
2019-10-17 00:29:21 +09:00
committed by Ludovic Fernandez
parent 29ef007917
commit 9f72b6d1d5
9 changed files with 2097 additions and 8 deletions
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8
Gopkg.lock generated
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@@ -1770,6 +1770,13 @@
pruneopts = "NUT"
revision = "1d7be4effb13d2d908342d349d71a284a7542693"
[[projects]]
digest = "1:9ca27be3cfd8a452f9814926a5842c6917289da8c21174ee0f9c79d84850b2ed"
name = "github.com/shopspring/decimal"
packages = ["."]
pruneopts = "NUT"
revision = "f1972eb1d1f519e2e5f4b51f2dea765e8c93a130"
[[projects]]
digest = "1:01252cd79aac70f16cac02a72a1067dd136e0ad6d5b597d0129cf74c739fd8d1"
name = "github.com/sirupsen/logrus"
@@ -2612,6 +2619,7 @@
"github.com/rancher/go-rancher-metadata/metadata",
"github.com/rancher/go-rancher/v2",
"github.com/ryanuber/go-glob",
"github.com/shopspring/decimal",
"github.com/sirupsen/logrus",
"github.com/stretchr/testify/assert",
"github.com/stretchr/testify/mock",

8
Gopkg.toml
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@@ -264,3 +264,11 @@
[[constraint]]
name = "github.com/google/uuid"
version = "0.2.0"
[[constraint]]
name = "github.com/shopspring/decimal"
revision = "f1972eb1d1f519e2e5f4b51f2dea765e8c93a130"
[[override]]
name = "contrib.go.opencensus.io/exporter/ocagent"
version = "0.4.12"

5
provider/kubernetes/percentage.go
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@@ -3,6 +3,8 @@ package kubernetes
import (
"strconv"
"strings"
"github.com/shopspring/decimal"
)
const defaultPercentageValuePrecision = 3
@@ -43,5 +45,6 @@ func newPercentageValueFromString(rawValue string) (percentageValue, error) {
// newPercentageValueFromFloat64 reads percentage value from float64
func newPercentageValueFromFloat64(f float64) percentageValue {
return percentageValue(f * (1000 * 100))
value := decimal.NewFromFloat(f).Mul(decimal.NewFromFloat(1000 * 100))
return percentageValue(value.IntPart())
}

22
provider/kubernetes/percentage_test.go
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@@ -74,46 +74,54 @@ func TestNewPercentageValueFromString(t *testing.T) {
}{
{
value: "1%",
expectError: false,
expectedString: "1.000%",
expectedFloat64: 0.01,
},
{
value: "0.5",
expectError: false,
expectedString: "0.500%",
expectedFloat64: 0.005,
},
{
value: "99%",
expectError: false,
expectedString: "99.000%",
expectedFloat64: 0.99,
},
{
value: "99.9%",
expectError: false,
expectedString: "99.900%",
expectedFloat64: 0.999,
},
{
value: "-99.9%",
expectError: false,
expectedString: "-99.900%",
expectedFloat64: -0.999,
},
{
value: "-99.99999%",
expectError: false,
expectedString: "-99.999%",
expectedFloat64: -0.99999,
},
{
value: "0%",
expectError: false,
expectedString: "0.000%",
expectedFloat64: 0,
},
{
value: "2.3%",
expectedString: "2.300%",
expectedFloat64: 0.023,
},
{
value: "5.1%",
expectedString: "5.100%",
expectedFloat64: 0.051,
},
{
value: "83.85%",
expectedString: "83.850%",
expectedFloat64: 0.83850,
},
{
value: "%",
expectError: true,

45
vendor/github.com/shopspring/decimal/LICENSE generated vendored Normal file
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@@ -0,0 +1,45 @@
The MIT License (MIT)
Copyright (c) 2015 Spring, Inc.
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
- Based on https://github.com/oguzbilgic/fpd, which has the following license:
"""
The MIT License (MIT)
Copyright (c) 2013 Oguz Bilgic
Permission is hereby granted, free of charge, to any person obtaining a copy of
this software and associated documentation files (the "Software"), to deal in
the Software without restriction, including without limitation the rights to
use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
the Software, and to permit persons to whom the Software is furnished to do so,
subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
"""

414
vendor/github.com/shopspring/decimal/decimal-go.go generated vendored Normal file
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@@ -0,0 +1,414 @@
// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Multiprecision decimal numbers.
// For floating-point formatting only; not general purpose.
// Only operations are assign and (binary) left/right shift.
// Can do binary floating point in multiprecision decimal precisely
// because 2 divides 10; cannot do decimal floating point
// in multiprecision binary precisely.
package decimal
type decimal struct {
d [800]byte // digits, big-endian representation
nd int // number of digits used
dp int // decimal point
neg bool // negative flag
trunc bool // discarded nonzero digits beyond d[:nd]
}
func (a *decimal) String() string {
n := 10 + a.nd
if a.dp > 0 {
n += a.dp
}
if a.dp < 0 {
n += -a.dp
}
buf := make([]byte, n)
w := 0
switch {
case a.nd == 0:
return "0"
case a.dp <= 0:
// zeros fill space between decimal point and digits
buf[w] = '0'
w++
buf[w] = '.'
w++
w += digitZero(buf[w : w+-a.dp])
w += copy(buf[w:], a.d[0:a.nd])
case a.dp < a.nd:
// decimal point in middle of digits
w += copy(buf[w:], a.d[0:a.dp])
buf[w] = '.'
w++
w += copy(buf[w:], a.d[a.dp:a.nd])
default:
// zeros fill space between digits and decimal point
w += copy(buf[w:], a.d[0:a.nd])
w += digitZero(buf[w : w+a.dp-a.nd])
}
return string(buf[0:w])
}
func digitZero(dst []byte) int {
for i := range dst {
dst[i] = '0'
}
return len(dst)
}
// trim trailing zeros from number.
// (They are meaningless; the decimal point is tracked
// independent of the number of digits.)
func trim(a *decimal) {
for a.nd > 0 && a.d[a.nd-1] == '0' {
a.nd--
}
if a.nd == 0 {
a.dp = 0
}
}
// Assign v to a.
func (a *decimal) Assign(v uint64) {
var buf [24]byte
// Write reversed decimal in buf.
n := 0
for v > 0 {
v1 := v / 10
v -= 10 * v1
buf[n] = byte(v + '0')
n++
v = v1
}
// Reverse again to produce forward decimal in a.d.
a.nd = 0
for n--; n >= 0; n-- {
a.d[a.nd] = buf[n]
a.nd++
}
a.dp = a.nd
trim(a)
}
// Maximum shift that we can do in one pass without overflow.
// A uint has 32 or 64 bits, and we have to be able to accommodate 9<<k.
const uintSize = 32 << (^uint(0) >> 63)
const maxShift = uintSize - 4
// Binary shift right (/ 2) by k bits. k <= maxShift to avoid overflow.
func rightShift(a *decimal, k uint) {
r := 0 // read pointer
w := 0 // write pointer
// Pick up enough leading digits to cover first shift.
var n uint
for ; n>>k == 0; r++ {
if r >= a.nd {
if n == 0 {
// a == 0; shouldn't get here, but handle anyway.
a.nd = 0
return
}
for n>>k == 0 {
n = n * 10
r++
}
break
}
c := uint(a.d[r])
n = n*10 + c - '0'
}
a.dp -= r - 1
var mask uint = (1 << k) - 1
// Pick up a digit, put down a digit.
for ; r < a.nd; r++ {
c := uint(a.d[r])
dig := n >> k
n &= mask
a.d[w] = byte(dig + '0')
w++
n = n*10 + c - '0'
}
// Put down extra digits.
for n > 0 {
dig := n >> k
n &= mask
if w < len(a.d) {
a.d[w] = byte(dig + '0')
w++
} else if dig > 0 {
a.trunc = true
}
n = n * 10
}
a.nd = w
trim(a)
}
// Cheat sheet for left shift: table indexed by shift count giving
// number of new digits that will be introduced by that shift.
//
// For example, leftcheats[4] = {2, "625"}. That means that
// if we are shifting by 4 (multiplying by 16), it will add 2 digits
// when the string prefix is "625" through "999", and one fewer digit
// if the string prefix is "000" through "624".
//
// Credit for this trick goes to Ken.
type leftCheat struct {
delta int // number of new digits
cutoff string // minus one digit if original < a.
}
var leftcheats = []leftCheat{
// Leading digits of 1/2^i = 5^i.
// 5^23 is not an exact 64-bit floating point number,
// so have to use bc for the math.
// Go up to 60 to be large enough for 32bit and 64bit platforms.
/*
seq 60 | sed 's/^/5^/' | bc |
awk 'BEGIN{ print "\t{ 0, \"\" }," }
{
log2 = log(2)/log(10)
printf("\t{ %d, \"%s\" },\t// * %d\n",
int(log2*NR+1), $0, 2**NR)
}'
*/
{0, ""},
{1, "5"}, // * 2
{1, "25"}, // * 4
{1, "125"}, // * 8
{2, "625"}, // * 16
{2, "3125"}, // * 32
{2, "15625"}, // * 64
{3, "78125"}, // * 128
{3, "390625"}, // * 256
{3, "1953125"}, // * 512
{4, "9765625"}, // * 1024
{4, "48828125"}, // * 2048
{4, "244140625"}, // * 4096
{4, "1220703125"}, // * 8192
{5, "6103515625"}, // * 16384
{5, "30517578125"}, // * 32768
{5, "152587890625"}, // * 65536
{6, "762939453125"}, // * 131072
{6, "3814697265625"}, // * 262144
{6, "19073486328125"}, // * 524288
{7, "95367431640625"}, // * 1048576
{7, "476837158203125"}, // * 2097152
{7, "2384185791015625"}, // * 4194304
{7, "11920928955078125"}, // * 8388608
{8, "59604644775390625"}, // * 16777216
{8, "298023223876953125"}, // * 33554432
{8, "1490116119384765625"}, // * 67108864
{9, "7450580596923828125"}, // * 134217728
{9, "37252902984619140625"}, // * 268435456
{9, "186264514923095703125"}, // * 536870912
{10, "931322574615478515625"}, // * 1073741824
{10, "4656612873077392578125"}, // * 2147483648
{10, "23283064365386962890625"}, // * 4294967296
{10, "116415321826934814453125"}, // * 8589934592
{11, "582076609134674072265625"}, // * 17179869184
{11, "2910383045673370361328125"}, // * 34359738368
{11, "14551915228366851806640625"}, // * 68719476736
{12, "72759576141834259033203125"}, // * 137438953472
{12, "363797880709171295166015625"}, // * 274877906944
{12, "1818989403545856475830078125"}, // * 549755813888
{13, "9094947017729282379150390625"}, // * 1099511627776
{13, "45474735088646411895751953125"}, // * 2199023255552
{13, "227373675443232059478759765625"}, // * 4398046511104
{13, "1136868377216160297393798828125"}, // * 8796093022208
{14, "5684341886080801486968994140625"}, // * 17592186044416
{14, "28421709430404007434844970703125"}, // * 35184372088832
{14, "142108547152020037174224853515625"}, // * 70368744177664
{15, "710542735760100185871124267578125"}, // * 140737488355328
{15, "3552713678800500929355621337890625"}, // * 281474976710656
{15, "17763568394002504646778106689453125"}, // * 562949953421312
{16, "88817841970012523233890533447265625"}, // * 1125899906842624
{16, "444089209850062616169452667236328125"}, // * 2251799813685248
{16, "2220446049250313080847263336181640625"}, // * 4503599627370496
{16, "11102230246251565404236316680908203125"}, // * 9007199254740992
{17, "55511151231257827021181583404541015625"}, // * 18014398509481984
{17, "277555756156289135105907917022705078125"}, // * 36028797018963968
{17, "1387778780781445675529539585113525390625"}, // * 72057594037927936
{18, "6938893903907228377647697925567626953125"}, // * 144115188075855872
{18, "34694469519536141888238489627838134765625"}, // * 288230376151711744
{18, "173472347597680709441192448139190673828125"}, // * 576460752303423488
{19, "867361737988403547205962240695953369140625"}, // * 1152921504606846976
}
// Is the leading prefix of b lexicographically less than s?
func prefixIsLessThan(b []byte, s string) bool {
for i := 0; i < len(s); i++ {
if i >= len(b) {
return true
}
if b[i] != s[i] {
return b[i] < s[i]
}
}
return false
}
// Binary shift left (* 2) by k bits. k <= maxShift to avoid overflow.
func leftShift(a *decimal, k uint) {
delta := leftcheats[k].delta
if prefixIsLessThan(a.d[0:a.nd], leftcheats[k].cutoff) {
delta--
}
r := a.nd // read index
w := a.nd + delta // write index
// Pick up a digit, put down a digit.
var n uint
for r--; r >= 0; r-- {
n += (uint(a.d[r]) - '0') << k
quo := n / 10
rem := n - 10*quo
w--
if w < len(a.d) {
a.d[w] = byte(rem + '0')
} else if rem != 0 {
a.trunc = true
}
n = quo
}
// Put down extra digits.
for n > 0 {
quo := n / 10
rem := n - 10*quo
w--
if w < len(a.d) {
a.d[w] = byte(rem + '0')
} else if rem != 0 {
a.trunc = true
}
n = quo
}
a.nd += delta
if a.nd >= len(a.d) {
a.nd = len(a.d)
}
a.dp += delta
trim(a)
}
// Binary shift left (k > 0) or right (k < 0).
func (a *decimal) Shift(k int) {
switch {
case a.nd == 0:
// nothing to do: a == 0
case k > 0:
for k > maxShift {
leftShift(a, maxShift)
k -= maxShift
}
leftShift(a, uint(k))
case k < 0:
for k < -maxShift {
rightShift(a, maxShift)
k += maxShift
}
rightShift(a, uint(-k))
}
}
// If we chop a at nd digits, should we round up?
func shouldRoundUp(a *decimal, nd int) bool {
if nd < 0 || nd >= a.nd {
return false
}
if a.d[nd] == '5' && nd+1 == a.nd { // exactly halfway - round to even
// if we truncated, a little higher than what's recorded - always round up
if a.trunc {
return true
}
return nd > 0 && (a.d[nd-1]-'0')%2 != 0
}
// not halfway - digit tells all
return a.d[nd] >= '5'
}
// Round a to nd digits (or fewer).
// If nd is zero, it means we're rounding
// just to the left of the digits, as in
// 0.09 -> 0.1.
func (a *decimal) Round(nd int) {
if nd < 0 || nd >= a.nd {
return
}
if shouldRoundUp(a, nd) {
a.RoundUp(nd)
} else {
a.RoundDown(nd)
}
}
// Round a down to nd digits (or fewer).
func (a *decimal) RoundDown(nd int) {
if nd < 0 || nd >= a.nd {
return
}
a.nd = nd
trim(a)
}
// Round a up to nd digits (or fewer).
func (a *decimal) RoundUp(nd int) {
if nd < 0 || nd >= a.nd {
return
}
// round up
for i := nd - 1; i >= 0; i-- {
c := a.d[i]
if c < '9' { // can stop after this digit
a.d[i]++
a.nd = i + 1
return
}
}
// Number is all 9s.
// Change to single 1 with adjusted decimal point.
a.d[0] = '1'
a.nd = 1
a.dp++
}
// Extract integer part, rounded appropriately.
// No guarantees about overflow.
func (a *decimal) RoundedInteger() uint64 {
if a.dp > 20 {
return 0xFFFFFFFFFFFFFFFF
}
var i int
n := uint64(0)
for i = 0; i < a.dp && i < a.nd; i++ {
n = n*10 + uint64(a.d[i]-'0')
}
for ; i < a.dp; i++ {
n *= 10
}
if shouldRoundUp(a, a.dp) {
n++
}
return n
}

1438
vendor/github.com/shopspring/decimal/decimal.go generated vendored Normal file
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47
vendor/github.com/shopspring/decimal/decomposer.go generated vendored Normal file
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@@ -0,0 +1,47 @@
package decimal
import (
"fmt"
"math/big"
)
// Decompose returns the internal decimal state into parts.
// If the provided buf has sufficient capacity, buf may be returned as the coefficient with
// the value set and length set as appropriate.
func (d Decimal) Decompose(buf []byte) (form byte, negative bool, coefficient []byte, exponent int32) {
negative = d.value.Sign() < 0
exponent = d.exp
coefficient = d.value.Bytes()
return
}
const (
decomposeFinite = 0
decomposeInfinite = 1
decomposeNaN = 2
)
// Compose sets the internal decimal value from parts. If the value cannot be
// represented then an error should be returned.
func (d *Decimal) Compose(form byte, negative bool, coefficient []byte, exponent int32) error {
switch form {
default:
return fmt.Errorf("unknown form: %v", form)
case decomposeFinite:
// Set rest of finite form below.
case decomposeInfinite:
return fmt.Errorf("Infinite form not supported")
case decomposeNaN:
return fmt.Errorf("NaN form not supported")
}
// Finite form.
if d.value == nil {
d.value = &big.Int{}
}
d.value.SetBytes(coefficient)
if negative && d.value.Sign() >= 0 {
d.value.Neg(d.value)
}
d.exp = exponent
return nil
}

118
vendor/github.com/shopspring/decimal/rounding.go generated vendored Normal file
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@@ -0,0 +1,118 @@
// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Multiprecision decimal numbers.
// For floating-point formatting only; not general purpose.
// Only operations are assign and (binary) left/right shift.
// Can do binary floating point in multiprecision decimal precisely
// because 2 divides 10; cannot do decimal floating point
// in multiprecision binary precisely.
package decimal
type floatInfo struct {
mantbits uint
expbits uint
bias int
}
var float32info = floatInfo{23, 8, -127}
var float64info = floatInfo{52, 11, -1023}
// roundShortest rounds d (= mant * 2^exp) to the shortest number of digits
// that will let the original floating point value be precisely reconstructed.
func roundShortest(d *decimal, mant uint64, exp int, flt *floatInfo) {
// If mantissa is zero, the number is zero; stop now.
if mant == 0 {
d.nd = 0
return
}
// Compute upper and lower such that any decimal number
// between upper and lower (possibly inclusive)
// will round to the original floating point number.
// We may see at once that the number is already shortest.
//
// Suppose d is not denormal, so that 2^exp <= d < 10^dp.
// The closest shorter number is at least 10^(dp-nd) away.
// The lower/upper bounds computed below are at distance
// at most 2^(exp-mantbits).
//
// So the number is already shortest if 10^(dp-nd) > 2^(exp-mantbits),
// or equivalently log2(10)*(dp-nd) > exp-mantbits.
// It is true if 332/100*(dp-nd) >= exp-mantbits (log2(10) > 3.32).
minexp := flt.bias + 1 // minimum possible exponent
if exp > minexp && 332*(d.dp-d.nd) >= 100*(exp-int(flt.mantbits)) {
// The number is already shortest.
return
}
// d = mant << (exp - mantbits)
// Next highest floating point number is mant+1 << exp-mantbits.
// Our upper bound is halfway between, mant*2+1 << exp-mantbits-1.
upper := new(decimal)
upper.Assign(mant*2 + 1)
upper.Shift(exp - int(flt.mantbits) - 1)
// d = mant << (exp - mantbits)
// Next lowest floating point number is mant-1 << exp-mantbits,
// unless mant-1 drops the significant bit and exp is not the minimum exp,
// in which case the next lowest is mant*2-1 << exp-mantbits-1.
// Either way, call it mantlo << explo-mantbits.
// Our lower bound is halfway between, mantlo*2+1 << explo-mantbits-1.
var mantlo uint64
var explo int
if mant > 1<<flt.mantbits || exp == minexp {
mantlo = mant - 1
explo = exp
} else {
mantlo = mant*2 - 1
explo = exp - 1
}
lower := new(decimal)
lower.Assign(mantlo*2 + 1)
lower.Shift(explo - int(flt.mantbits) - 1)
// The upper and lower bounds are possible outputs only if
// the original mantissa is even, so that IEEE round-to-even
// would round to the original mantissa and not the neighbors.
inclusive := mant%2 == 0
// Now we can figure out the minimum number of digits required.
// Walk along until d has distinguished itself from upper and lower.
for i := 0; i < d.nd; i++ {
l := byte('0') // lower digit
if i < lower.nd {
l = lower.d[i]
}
m := d.d[i] // middle digit
u := byte('0') // upper digit
if i < upper.nd {
u = upper.d[i]
}
// Okay to round down (truncate) if lower has a different digit
// or if lower is inclusive and is exactly the result of rounding
// down (i.e., and we have reached the final digit of lower).
okdown := l != m || inclusive && i+1 == lower.nd
// Okay to round up if upper has a different digit and either upper
// is inclusive or upper is bigger than the result of rounding up.
okup := m != u && (inclusive || m+1 < u || i+1 < upper.nd)
// If it's okay to do either, then round to the nearest one.
// If it's okay to do only one, do it.
switch {
case okdown && okup:
d.Round(i + 1)
return
case okdown:
d.RoundDown(i + 1)
return
case okup:
d.RoundUp(i + 1)
return
}
}
}