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gitea/vendor/github.com/RoaringBitmap/roaring/roaring.go

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// Package roaring is an implementation of Roaring Bitmaps in Go.
// They provide fast compressed bitmap data structures (also called bitset).
// They are ideally suited to represent sets of integers over
// relatively small ranges.
// See http://roaringbitmap.org for details.
package roaring
import (
"bytes"
"encoding/base64"
"fmt"
"io"
"strconv"
"sync"
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)
// Bitmap represents a compressed bitmap where you can add integers.
type Bitmap struct {
highlowcontainer roaringArray
}
// ToBase64 serializes a bitmap as Base64
func (rb *Bitmap) ToBase64() (string, error) {
buf := new(bytes.Buffer)
_, err := rb.WriteTo(buf)
return base64.StdEncoding.EncodeToString(buf.Bytes()), err
}
// FromBase64 deserializes a bitmap from Base64
func (rb *Bitmap) FromBase64(str string) (int64, error) {
data, err := base64.StdEncoding.DecodeString(str)
if err != nil {
return 0, err
}
buf := bytes.NewBuffer(data)
return rb.ReadFrom(buf)
}
// WriteTo writes a serialized version of this bitmap to stream.
// The format is compatible with other RoaringBitmap
// implementations (Java, C) and is documented here:
// https://github.com/RoaringBitmap/RoaringFormatSpec
func (rb *Bitmap) WriteTo(stream io.Writer) (int64, error) {
return rb.highlowcontainer.writeTo(stream)
}
// ToBytes returns an array of bytes corresponding to what is written
// when calling WriteTo
func (rb *Bitmap) ToBytes() ([]byte, error) {
return rb.highlowcontainer.toBytes()
}
// Deprecated: WriteToMsgpack writes a msgpack2/snappy-streaming compressed serialized
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// version of this bitmap to stream. The format is not
// compatible with the WriteTo() format, and is
// experimental: it may produce smaller on disk
// footprint and/or be faster to read, depending
// on your content. Currently only the Go roaring
// implementation supports this format.
func (rb *Bitmap) WriteToMsgpack(stream io.Writer) (int64, error) {
return 0, rb.highlowcontainer.writeToMsgpack(stream)
}
// ReadFrom reads a serialized version of this bitmap from stream.
// The format is compatible with other RoaringBitmap
// implementations (Java, C) and is documented here:
// https://github.com/RoaringBitmap/RoaringFormatSpec
func (rb *Bitmap) ReadFrom(reader io.Reader) (p int64, err error) {
stream := byteInputAdapterPool.Get().(*byteInputAdapter)
stream.reset(reader)
p, err = rb.highlowcontainer.readFrom(stream)
byteInputAdapterPool.Put(stream)
return
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}
// FromBuffer creates a bitmap from its serialized version stored in buffer
//
// The format specification is available here:
// https://github.com/RoaringBitmap/RoaringFormatSpec
//
// The provided byte array (buf) is expected to be a constant.
// The function makes the best effort attempt not to copy data.
// You should take care not to modify buff as it will
// likely result in unexpected program behavior.
//
// Resulting bitmaps are effectively immutable in the following sense:
// a copy-on-write marker is used so that when you modify the resulting
// bitmap, copies of selected data (containers) are made.
// You should *not* change the copy-on-write status of the resulting
// bitmaps (SetCopyOnWrite).
//
// If buf becomes unavailable, then a bitmap created with
// FromBuffer would be effectively broken. Furthermore, any
// bitmap derived from this bitmap (e.g., via Or, And) might
// also be broken. Thus, before making buf unavailable, you should
// call CloneCopyOnWriteContainers on all such bitmaps.
//
func (rb *Bitmap) FromBuffer(buf []byte) (p int64, err error) {
stream := byteBufferPool.Get().(*byteBuffer)
stream.reset(buf)
p, err = rb.highlowcontainer.readFrom(stream)
byteBufferPool.Put(stream)
return
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}
var (
byteBufferPool = sync.Pool{
New: func() interface{} {
return &byteBuffer{}
},
}
byteInputAdapterPool = sync.Pool{
New: func() interface{} {
return &byteInputAdapter{}
},
}
)
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// RunOptimize attempts to further compress the runs of consecutive values found in the bitmap
func (rb *Bitmap) RunOptimize() {
rb.highlowcontainer.runOptimize()
}
// HasRunCompression returns true if the bitmap benefits from run compression
func (rb *Bitmap) HasRunCompression() bool {
return rb.highlowcontainer.hasRunCompression()
}
// Deprecated: ReadFromMsgpack reads a msgpack2/snappy-streaming serialized
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// version of this bitmap from stream. The format is
// expected is that written by the WriteToMsgpack()
// call; see additional notes there.
func (rb *Bitmap) ReadFromMsgpack(stream io.Reader) (int64, error) {
return 0, rb.highlowcontainer.readFromMsgpack(stream)
}
// MarshalBinary implements the encoding.BinaryMarshaler interface for the bitmap
// (same as ToBytes)
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func (rb *Bitmap) MarshalBinary() ([]byte, error) {
return rb.ToBytes()
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}
// UnmarshalBinary implements the encoding.BinaryUnmarshaler interface for the bitmap
func (rb *Bitmap) UnmarshalBinary(data []byte) error {
r := bytes.NewReader(data)
_, err := rb.ReadFrom(r)
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return err
}
// NewBitmap creates a new empty Bitmap (see also New)
func NewBitmap() *Bitmap {
return &Bitmap{}
}
// New creates a new empty Bitmap (same as NewBitmap)
func New() *Bitmap {
return &Bitmap{}
}
// Clear resets the Bitmap to be logically empty, but may retain
// some memory allocations that may speed up future operations
func (rb *Bitmap) Clear() {
rb.highlowcontainer.clear()
}
// ToArray creates a new slice containing all of the integers stored in the Bitmap in sorted order
func (rb *Bitmap) ToArray() []uint32 {
array := make([]uint32, rb.GetCardinality())
pos := 0
pos2 := 0
for pos < rb.highlowcontainer.size() {
hs := uint32(rb.highlowcontainer.getKeyAtIndex(pos)) << 16
c := rb.highlowcontainer.getContainerAtIndex(pos)
pos++
c.fillLeastSignificant16bits(array, pos2, hs)
pos2 += c.getCardinality()
}
return array
}
// GetSizeInBytes estimates the memory usage of the Bitmap. Note that this
// might differ slightly from the amount of bytes required for persistent storage
func (rb *Bitmap) GetSizeInBytes() uint64 {
size := uint64(8)
for _, c := range rb.highlowcontainer.containers {
size += uint64(2) + uint64(c.getSizeInBytes())
}
return size
}
// GetSerializedSizeInBytes computes the serialized size in bytes
// of the Bitmap. It should correspond to the
// number of bytes written when invoking WriteTo. You can expect
// that this function is much cheaper computationally than WriteTo.
func (rb *Bitmap) GetSerializedSizeInBytes() uint64 {
return rb.highlowcontainer.serializedSizeInBytes()
}
// BoundSerializedSizeInBytes returns an upper bound on the serialized size in bytes
// assuming that one wants to store "cardinality" integers in [0, universe_size)
func BoundSerializedSizeInBytes(cardinality uint64, universeSize uint64) uint64 {
contnbr := (universeSize + uint64(65535)) / uint64(65536)
if contnbr > cardinality {
contnbr = cardinality
// we can't have more containers than we have values
}
headermax := 8*contnbr + 4
if 4 > (contnbr+7)/8 {
headermax += 4
} else {
headermax += (contnbr + 7) / 8
}
valsarray := uint64(arrayContainerSizeInBytes(int(cardinality)))
valsbitmap := contnbr * uint64(bitmapContainerSizeInBytes())
valsbest := valsarray
if valsbest > valsbitmap {
valsbest = valsbitmap
}
return valsbest + headermax
}
// IntIterable allows you to iterate over the values in a Bitmap
type IntIterable interface {
HasNext() bool
Next() uint32
}
// IntPeekable allows you to look at the next value without advancing and
// advance as long as the next value is smaller than minval
type IntPeekable interface {
IntIterable
// PeekNext peeks the next value without advancing the iterator
PeekNext() uint32
// AdvanceIfNeeded advances as long as the next value is smaller than minval
AdvanceIfNeeded(minval uint32)
}
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type intIterator struct {
pos int
hs uint32
iter shortPeekable
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highlowcontainer *roaringArray
}
// HasNext returns true if there are more integers to iterate over
func (ii *intIterator) HasNext() bool {
return ii.pos < ii.highlowcontainer.size()
}
func (ii *intIterator) init() {
if ii.highlowcontainer.size() > ii.pos {
ii.iter = ii.highlowcontainer.getContainerAtIndex(ii.pos).getShortIterator()
ii.hs = uint32(ii.highlowcontainer.getKeyAtIndex(ii.pos)) << 16
}
}
// Next returns the next integer
func (ii *intIterator) Next() uint32 {
x := uint32(ii.iter.next()) | ii.hs
if !ii.iter.hasNext() {
ii.pos = ii.pos + 1
ii.init()
}
return x
}
// PeekNext peeks the next value without advancing the iterator
func (ii *intIterator) PeekNext() uint32 {
return uint32(ii.iter.peekNext()&maxLowBit) | ii.hs
}
// AdvanceIfNeeded advances as long as the next value is smaller than minval
func (ii *intIterator) AdvanceIfNeeded(minval uint32) {
to := minval >> 16
for ii.HasNext() && (ii.hs>>16) < to {
ii.pos++
ii.init()
}
if ii.HasNext() && (ii.hs>>16) == to {
ii.iter.advanceIfNeeded(lowbits(minval))
if !ii.iter.hasNext() {
ii.pos++
ii.init()
}
}
}
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func newIntIterator(a *Bitmap) *intIterator {
p := new(intIterator)
p.pos = 0
p.highlowcontainer = &a.highlowcontainer
p.init()
return p
}
type intReverseIterator struct {
pos int
hs uint32
iter shortIterable
highlowcontainer *roaringArray
}
// HasNext returns true if there are more integers to iterate over
func (ii *intReverseIterator) HasNext() bool {
return ii.pos >= 0
}
func (ii *intReverseIterator) init() {
if ii.pos >= 0 {
ii.iter = ii.highlowcontainer.getContainerAtIndex(ii.pos).getReverseIterator()
ii.hs = uint32(ii.highlowcontainer.getKeyAtIndex(ii.pos)) << 16
} else {
ii.iter = nil
}
}
// Next returns the next integer
func (ii *intReverseIterator) Next() uint32 {
x := uint32(ii.iter.next()) | ii.hs
if !ii.iter.hasNext() {
ii.pos = ii.pos - 1
ii.init()
}
return x
}
func newIntReverseIterator(a *Bitmap) *intReverseIterator {
p := new(intReverseIterator)
p.highlowcontainer = &a.highlowcontainer
p.pos = a.highlowcontainer.size() - 1
p.init()
return p
}
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// ManyIntIterable allows you to iterate over the values in a Bitmap
type ManyIntIterable interface {
// NextMany fills buf up with values, returns how many values were returned
NextMany(buf []uint32) int
// NextMany64 fills up buf with 64 bit values, uses hs as a mask (OR), returns how many values were returned
NextMany64(hs uint64, buf []uint64) int
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}
type manyIntIterator struct {
pos int
hs uint32
iter manyIterable
highlowcontainer *roaringArray
}
func (ii *manyIntIterator) init() {
if ii.highlowcontainer.size() > ii.pos {
ii.iter = ii.highlowcontainer.getContainerAtIndex(ii.pos).getManyIterator()
ii.hs = uint32(ii.highlowcontainer.getKeyAtIndex(ii.pos)) << 16
} else {
ii.iter = nil
}
}
func (ii *manyIntIterator) NextMany(buf []uint32) int {
n := 0
for n < len(buf) {
if ii.iter == nil {
break
}
moreN := ii.iter.nextMany(ii.hs, buf[n:])
n += moreN
if moreN == 0 {
ii.pos = ii.pos + 1
ii.init()
}
}
return n
}
func (ii *manyIntIterator) NextMany64(hs64 uint64, buf []uint64) int {
n := 0
for n < len(buf) {
if ii.iter == nil {
break
}
hs := uint64(ii.hs) | hs64
moreN := ii.iter.nextMany64(hs, buf[n:])
n += moreN
if moreN == 0 {
ii.pos = ii.pos + 1
ii.init()
}
}
return n
}
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func newManyIntIterator(a *Bitmap) *manyIntIterator {
p := new(manyIntIterator)
p.pos = 0
p.highlowcontainer = &a.highlowcontainer
p.init()
return p
}
// String creates a string representation of the Bitmap
func (rb *Bitmap) String() string {
// inspired by https://github.com/fzandona/goroar/
var buffer bytes.Buffer
start := []byte("{")
buffer.Write(start)
i := rb.Iterator()
counter := 0
if i.HasNext() {
counter = counter + 1
buffer.WriteString(strconv.FormatInt(int64(i.Next()), 10))
}
for i.HasNext() {
buffer.WriteString(",")
counter = counter + 1
// to avoid exhausting the memory
if counter > 0x40000 {
buffer.WriteString("...")
break
}
buffer.WriteString(strconv.FormatInt(int64(i.Next()), 10))
}
buffer.WriteString("}")
return buffer.String()
}
// Iterate iterates over the bitmap, calling the given callback with each value in the bitmap. If the callback returns
// false, the iteration is halted.
// The iteration results are undefined if the bitmap is modified (e.g., with Add or Remove).
// There is no guarantee as to what order the values will be iterated
func (rb *Bitmap) Iterate(cb func(x uint32) bool) {
for i := 0; i < rb.highlowcontainer.size(); i++ {
hs := uint32(rb.highlowcontainer.getKeyAtIndex(i)) << 16
c := rb.highlowcontainer.getContainerAtIndex(i)
var shouldContinue bool
// This is hacky but it avoids allocations from invoking an interface method with a closure
switch t := c.(type) {
case *arrayContainer:
shouldContinue = t.iterate(func(x uint16) bool {
return cb(uint32(x) | hs)
})
case *runContainer16:
shouldContinue = t.iterate(func(x uint16) bool {
return cb(uint32(x) | hs)
})
case *bitmapContainer:
shouldContinue = t.iterate(func(x uint16) bool {
return cb(uint32(x) | hs)
})
}
if !shouldContinue {
break
}
}
}
// Iterator creates a new IntPeekable to iterate over the integers contained in the bitmap, in sorted order;
// the iterator becomes invalid if the bitmap is modified (e.g., with Add or Remove).
func (rb *Bitmap) Iterator() IntPeekable {
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return newIntIterator(rb)
}
// ReverseIterator creates a new IntIterable to iterate over the integers contained in the bitmap, in sorted order;
// the iterator becomes invalid if the bitmap is modified (e.g., with Add or Remove).
func (rb *Bitmap) ReverseIterator() IntIterable {
return newIntReverseIterator(rb)
}
// ManyIterator creates a new ManyIntIterable to iterate over the integers contained in the bitmap, in sorted order;
// the iterator becomes invalid if the bitmap is modified (e.g., with Add or Remove).
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func (rb *Bitmap) ManyIterator() ManyIntIterable {
return newManyIntIterator(rb)
}
// Clone creates a copy of the Bitmap
func (rb *Bitmap) Clone() *Bitmap {
ptr := new(Bitmap)
ptr.highlowcontainer = *rb.highlowcontainer.clone()
return ptr
}
// Minimum get the smallest value stored in this roaring bitmap, assumes that it is not empty
func (rb *Bitmap) Minimum() uint32 {
return uint32(rb.highlowcontainer.containers[0].minimum()) | (uint32(rb.highlowcontainer.keys[0]) << 16)
}
// Maximum get the largest value stored in this roaring bitmap, assumes that it is not empty
func (rb *Bitmap) Maximum() uint32 {
lastindex := len(rb.highlowcontainer.containers) - 1
return uint32(rb.highlowcontainer.containers[lastindex].maximum()) | (uint32(rb.highlowcontainer.keys[lastindex]) << 16)
}
// Contains returns true if the integer is contained in the bitmap
func (rb *Bitmap) Contains(x uint32) bool {
hb := highbits(x)
c := rb.highlowcontainer.getContainer(hb)
return c != nil && c.contains(lowbits(x))
}
// ContainsInt returns true if the integer is contained in the bitmap (this is a convenience method, the parameter is casted to uint32 and Contains is called)
func (rb *Bitmap) ContainsInt(x int) bool {
return rb.Contains(uint32(x))
}
// Equals returns true if the two bitmaps contain the same integers
func (rb *Bitmap) Equals(o interface{}) bool {
srb, ok := o.(*Bitmap)
if ok {
return srb.highlowcontainer.equals(rb.highlowcontainer)
}
return false
}
// AddOffset adds the value 'offset' to each and every value in a bitmap, generating a new bitmap in the process
func AddOffset(x *Bitmap, offset uint32) (answer *Bitmap) {
return AddOffset64(x, int64(offset))
}
// AddOffset64 adds the value 'offset' to each and every value in a bitmap, generating a new bitmap in the process
// If offset + element is outside of the range [0,2^32), that the element will be dropped
func AddOffset64(x *Bitmap, offset int64) (answer *Bitmap) {
// we need "offset" to be a long because we want to support values
// between -0xFFFFFFFF up to +-0xFFFFFFFF
var containerOffset64 int64
if offset < 0 {
containerOffset64 = (offset - (1 << 16) + 1) / (1 << 16)
} else {
containerOffset64 = offset >> 16
}
if containerOffset64 >= (1<<16) || containerOffset64 <= -(1<<16) {
return New()
}
containerOffset := int32(containerOffset64)
inOffset := (uint16)(offset - containerOffset64*(1<<16))
if inOffset == 0 {
answer = x.Clone()
for pos := 0; pos < answer.highlowcontainer.size(); pos++ {
key := int32(answer.highlowcontainer.getKeyAtIndex(pos))
key += containerOffset
if key >= 0 && key <= MaxUint16 {
answer.highlowcontainer.keys[pos] = uint16(key)
}
}
} else {
answer = New()
for pos := 0; pos < x.highlowcontainer.size(); pos++ {
key := int32(x.highlowcontainer.getKeyAtIndex(pos))
key += containerOffset
c := x.highlowcontainer.getContainerAtIndex(pos)
offsetted := c.addOffset(inOffset)
if offsetted[0].getCardinality() > 0 && (key >= 0 && key <= MaxUint16) {
curSize := answer.highlowcontainer.size()
lastkey := int32(0)
if curSize > 0 {
lastkey = int32(answer.highlowcontainer.getKeyAtIndex(curSize - 1))
}
if curSize > 0 && lastkey == key {
prev := answer.highlowcontainer.getContainerAtIndex(curSize - 1)
orrseult := prev.ior(offsetted[0])
answer.highlowcontainer.setContainerAtIndex(curSize-1, orrseult)
} else {
answer.highlowcontainer.appendContainer(uint16(key), offsetted[0], false)
}
}
if offsetted[1].getCardinality() > 0 && ((key+1) >= 0 && (key+1) <= MaxUint16) {
answer.highlowcontainer.appendContainer(uint16(key+1), offsetted[1], false)
}
}
}
return answer
}
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// Add the integer x to the bitmap
func (rb *Bitmap) Add(x uint32) {
hb := highbits(x)
ra := &rb.highlowcontainer
i := ra.getIndex(hb)
if i >= 0 {
var c container
c = ra.getWritableContainerAtIndex(i).iaddReturnMinimized(lowbits(x))
rb.highlowcontainer.setContainerAtIndex(i, c)
} else {
newac := newArrayContainer()
rb.highlowcontainer.insertNewKeyValueAt(-i-1, hb, newac.iaddReturnMinimized(lowbits(x)))
}
}
// add the integer x to the bitmap, return the container and its index
func (rb *Bitmap) addwithptr(x uint32) (int, container) {
hb := highbits(x)
ra := &rb.highlowcontainer
i := ra.getIndex(hb)
var c container
if i >= 0 {
c = ra.getWritableContainerAtIndex(i).iaddReturnMinimized(lowbits(x))
rb.highlowcontainer.setContainerAtIndex(i, c)
return i, c
}
newac := newArrayContainer()
c = newac.iaddReturnMinimized(lowbits(x))
rb.highlowcontainer.insertNewKeyValueAt(-i-1, hb, c)
return -i - 1, c
}
// CheckedAdd adds the integer x to the bitmap and return true if it was added (false if the integer was already present)
func (rb *Bitmap) CheckedAdd(x uint32) bool {
// TODO: add unit tests for this method
hb := highbits(x)
i := rb.highlowcontainer.getIndex(hb)
if i >= 0 {
C := rb.highlowcontainer.getWritableContainerAtIndex(i)
oldcard := C.getCardinality()
C = C.iaddReturnMinimized(lowbits(x))
rb.highlowcontainer.setContainerAtIndex(i, C)
return C.getCardinality() > oldcard
}
newac := newArrayContainer()
rb.highlowcontainer.insertNewKeyValueAt(-i-1, hb, newac.iaddReturnMinimized(lowbits(x)))
return true
}
// AddInt adds the integer x to the bitmap (convenience method: the parameter is casted to uint32 and we call Add)
func (rb *Bitmap) AddInt(x int) {
rb.Add(uint32(x))
}
// Remove the integer x from the bitmap
func (rb *Bitmap) Remove(x uint32) {
hb := highbits(x)
i := rb.highlowcontainer.getIndex(hb)
if i >= 0 {
c := rb.highlowcontainer.getWritableContainerAtIndex(i).iremoveReturnMinimized(lowbits(x))
rb.highlowcontainer.setContainerAtIndex(i, c)
if rb.highlowcontainer.getContainerAtIndex(i).getCardinality() == 0 {
rb.highlowcontainer.removeAtIndex(i)
}
}
}
// CheckedRemove removes the integer x from the bitmap and return true if the integer was effectively remove (and false if the integer was not present)
func (rb *Bitmap) CheckedRemove(x uint32) bool {
// TODO: add unit tests for this method
hb := highbits(x)
i := rb.highlowcontainer.getIndex(hb)
if i >= 0 {
C := rb.highlowcontainer.getWritableContainerAtIndex(i)
oldcard := C.getCardinality()
C = C.iremoveReturnMinimized(lowbits(x))
rb.highlowcontainer.setContainerAtIndex(i, C)
if rb.highlowcontainer.getContainerAtIndex(i).getCardinality() == 0 {
rb.highlowcontainer.removeAtIndex(i)
return true
}
return C.getCardinality() < oldcard
}
return false
}
// IsEmpty returns true if the Bitmap is empty (it is faster than doing (GetCardinality() == 0))
func (rb *Bitmap) IsEmpty() bool {
return rb.highlowcontainer.size() == 0
}
// GetCardinality returns the number of integers contained in the bitmap
func (rb *Bitmap) GetCardinality() uint64 {
size := uint64(0)
for _, c := range rb.highlowcontainer.containers {
size += uint64(c.getCardinality())
}
return size
}
// Rank returns the number of integers that are smaller or equal to x (Rank(infinity) would be GetCardinality()).
// If you pass the smallest value, you get the value 1. If you pass a value that is smaller than the smallest
// value, you get 0. Note that this function differs in convention from the Select function since it
// return 1 and not 0 on the smallest value.
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func (rb *Bitmap) Rank(x uint32) uint64 {
size := uint64(0)
for i := 0; i < rb.highlowcontainer.size(); i++ {
key := rb.highlowcontainer.getKeyAtIndex(i)
if key > highbits(x) {
return size
}
if key < highbits(x) {
size += uint64(rb.highlowcontainer.getContainerAtIndex(i).getCardinality())
} else {
return size + uint64(rb.highlowcontainer.getContainerAtIndex(i).rank(lowbits(x)))
}
}
return size
}
// Select returns the xth integer in the bitmap. If you pass 0, you get
// the smallest element. Note that this function differs in convention from
// the Rank function which returns 1 on the smallest value.
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func (rb *Bitmap) Select(x uint32) (uint32, error) {
if rb.GetCardinality() <= uint64(x) {
return 0, fmt.Errorf("can't find %dth integer in a bitmap with only %d items", x, rb.GetCardinality())
}
remaining := x
for i := 0; i < rb.highlowcontainer.size(); i++ {
c := rb.highlowcontainer.getContainerAtIndex(i)
if remaining >= uint32(c.getCardinality()) {
remaining -= uint32(c.getCardinality())
} else {
key := rb.highlowcontainer.getKeyAtIndex(i)
return uint32(key)<<16 + uint32(c.selectInt(uint16(remaining))), nil
}
}
return 0, fmt.Errorf("can't find %dth integer in a bitmap with only %d items", x, rb.GetCardinality())
}
// And computes the intersection between two bitmaps and stores the result in the current bitmap
func (rb *Bitmap) And(x2 *Bitmap) {
pos1 := 0
pos2 := 0
intersectionsize := 0
length1 := rb.highlowcontainer.size()
length2 := x2.highlowcontainer.size()
main:
for {
if pos1 < length1 && pos2 < length2 {
s1 := rb.highlowcontainer.getKeyAtIndex(pos1)
s2 := x2.highlowcontainer.getKeyAtIndex(pos2)
for {
if s1 == s2 {
c1 := rb.highlowcontainer.getWritableContainerAtIndex(pos1)
c2 := x2.highlowcontainer.getContainerAtIndex(pos2)
diff := c1.iand(c2)
if diff.getCardinality() > 0 {
rb.highlowcontainer.replaceKeyAndContainerAtIndex(intersectionsize, s1, diff, false)
intersectionsize++
}
pos1++
pos2++
if (pos1 == length1) || (pos2 == length2) {
break main
}
s1 = rb.highlowcontainer.getKeyAtIndex(pos1)
s2 = x2.highlowcontainer.getKeyAtIndex(pos2)
} else if s1 < s2 {
pos1 = rb.highlowcontainer.advanceUntil(s2, pos1)
if pos1 == length1 {
break main
}
s1 = rb.highlowcontainer.getKeyAtIndex(pos1)
} else { //s1 > s2
pos2 = x2.highlowcontainer.advanceUntil(s1, pos2)
if pos2 == length2 {
break main
}
s2 = x2.highlowcontainer.getKeyAtIndex(pos2)
}
}
} else {
break
}
}
rb.highlowcontainer.resize(intersectionsize)
}
// OrCardinality returns the cardinality of the union between two bitmaps, bitmaps are not modified
func (rb *Bitmap) OrCardinality(x2 *Bitmap) uint64 {
pos1 := 0
pos2 := 0
length1 := rb.highlowcontainer.size()
length2 := x2.highlowcontainer.size()
answer := uint64(0)
main:
for {
if (pos1 < length1) && (pos2 < length2) {
s1 := rb.highlowcontainer.getKeyAtIndex(pos1)
s2 := x2.highlowcontainer.getKeyAtIndex(pos2)
for {
if s1 < s2 {
answer += uint64(rb.highlowcontainer.getContainerAtIndex(pos1).getCardinality())
pos1++
if pos1 == length1 {
break main
}
s1 = rb.highlowcontainer.getKeyAtIndex(pos1)
} else if s1 > s2 {
answer += uint64(x2.highlowcontainer.getContainerAtIndex(pos2).getCardinality())
pos2++
if pos2 == length2 {
break main
}
s2 = x2.highlowcontainer.getKeyAtIndex(pos2)
} else {
// TODO: could be faster if we did not have to materialize the container
answer += uint64(rb.highlowcontainer.getContainerAtIndex(pos1).or(x2.highlowcontainer.getContainerAtIndex(pos2)).getCardinality())
pos1++
pos2++
if (pos1 == length1) || (pos2 == length2) {
break main
}
s1 = rb.highlowcontainer.getKeyAtIndex(pos1)
s2 = x2.highlowcontainer.getKeyAtIndex(pos2)
}
}
} else {
break
}
}
for ; pos1 < length1; pos1++ {
answer += uint64(rb.highlowcontainer.getContainerAtIndex(pos1).getCardinality())
}
for ; pos2 < length2; pos2++ {
answer += uint64(x2.highlowcontainer.getContainerAtIndex(pos2).getCardinality())
}
return answer
}
// AndCardinality returns the cardinality of the intersection between two bitmaps, bitmaps are not modified
func (rb *Bitmap) AndCardinality(x2 *Bitmap) uint64 {
pos1 := 0
pos2 := 0
answer := uint64(0)
length1 := rb.highlowcontainer.size()
length2 := x2.highlowcontainer.size()
main:
for {
if pos1 < length1 && pos2 < length2 {
s1 := rb.highlowcontainer.getKeyAtIndex(pos1)
s2 := x2.highlowcontainer.getKeyAtIndex(pos2)
for {
if s1 == s2 {
c1 := rb.highlowcontainer.getContainerAtIndex(pos1)
c2 := x2.highlowcontainer.getContainerAtIndex(pos2)
answer += uint64(c1.andCardinality(c2))
pos1++
pos2++
if (pos1 == length1) || (pos2 == length2) {
break main
}
s1 = rb.highlowcontainer.getKeyAtIndex(pos1)
s2 = x2.highlowcontainer.getKeyAtIndex(pos2)
} else if s1 < s2 {
pos1 = rb.highlowcontainer.advanceUntil(s2, pos1)
if pos1 == length1 {
break main
}
s1 = rb.highlowcontainer.getKeyAtIndex(pos1)
} else { //s1 > s2
pos2 = x2.highlowcontainer.advanceUntil(s1, pos2)
if pos2 == length2 {
break main
}
s2 = x2.highlowcontainer.getKeyAtIndex(pos2)
}
}
} else {
break
}
}
return answer
}
// Intersects checks whether two bitmap intersects, bitmaps are not modified
func (rb *Bitmap) Intersects(x2 *Bitmap) bool {
pos1 := 0
pos2 := 0
length1 := rb.highlowcontainer.size()
length2 := x2.highlowcontainer.size()
main:
for {
if pos1 < length1 && pos2 < length2 {
s1 := rb.highlowcontainer.getKeyAtIndex(pos1)
s2 := x2.highlowcontainer.getKeyAtIndex(pos2)
for {
if s1 == s2 {
c1 := rb.highlowcontainer.getContainerAtIndex(pos1)
c2 := x2.highlowcontainer.getContainerAtIndex(pos2)
if c1.intersects(c2) {
return true
}
pos1++
pos2++
if (pos1 == length1) || (pos2 == length2) {
break main
}
s1 = rb.highlowcontainer.getKeyAtIndex(pos1)
s2 = x2.highlowcontainer.getKeyAtIndex(pos2)
} else if s1 < s2 {
pos1 = rb.highlowcontainer.advanceUntil(s2, pos1)
if pos1 == length1 {
break main
}
s1 = rb.highlowcontainer.getKeyAtIndex(pos1)
} else { //s1 > s2
pos2 = x2.highlowcontainer.advanceUntil(s1, pos2)
if pos2 == length2 {
break main
}
s2 = x2.highlowcontainer.getKeyAtIndex(pos2)
}
}
} else {
break
}
}
return false
}
// Xor computes the symmetric difference between two bitmaps and stores the result in the current bitmap
func (rb *Bitmap) Xor(x2 *Bitmap) {
pos1 := 0
pos2 := 0
length1 := rb.highlowcontainer.size()
length2 := x2.highlowcontainer.size()
for {
if (pos1 < length1) && (pos2 < length2) {
s1 := rb.highlowcontainer.getKeyAtIndex(pos1)
s2 := x2.highlowcontainer.getKeyAtIndex(pos2)
if s1 < s2 {
pos1 = rb.highlowcontainer.advanceUntil(s2, pos1)
if pos1 == length1 {
break
}
} else if s1 > s2 {
c := x2.highlowcontainer.getWritableContainerAtIndex(pos2)
rb.highlowcontainer.insertNewKeyValueAt(pos1, x2.highlowcontainer.getKeyAtIndex(pos2), c)
length1++
pos1++
pos2++
} else {
// TODO: couple be computed in-place for reduced memory usage
c := rb.highlowcontainer.getContainerAtIndex(pos1).xor(x2.highlowcontainer.getContainerAtIndex(pos2))
if c.getCardinality() > 0 {
rb.highlowcontainer.setContainerAtIndex(pos1, c)
pos1++
} else {
rb.highlowcontainer.removeAtIndex(pos1)
length1--
}
pos2++
}
} else {
break
}
}
if pos1 == length1 {
rb.highlowcontainer.appendCopyMany(x2.highlowcontainer, pos2, length2)
}
}
// Or computes the union between two bitmaps and stores the result in the current bitmap
func (rb *Bitmap) Or(x2 *Bitmap) {
pos1 := 0
pos2 := 0
length1 := rb.highlowcontainer.size()
length2 := x2.highlowcontainer.size()
main:
for (pos1 < length1) && (pos2 < length2) {
s1 := rb.highlowcontainer.getKeyAtIndex(pos1)
s2 := x2.highlowcontainer.getKeyAtIndex(pos2)
for {
if s1 < s2 {
pos1++
if pos1 == length1 {
break main
}
s1 = rb.highlowcontainer.getKeyAtIndex(pos1)
} else if s1 > s2 {
rb.highlowcontainer.insertNewKeyValueAt(pos1, s2, x2.highlowcontainer.getContainerAtIndex(pos2).clone())
pos1++
length1++
pos2++
if pos2 == length2 {
break main
}
s2 = x2.highlowcontainer.getKeyAtIndex(pos2)
} else {
rb.highlowcontainer.replaceKeyAndContainerAtIndex(pos1, s1, rb.highlowcontainer.getUnionedWritableContainer(pos1, x2.highlowcontainer.getContainerAtIndex(pos2)), false)
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pos1++
pos2++
if (pos1 == length1) || (pos2 == length2) {
break main
}
s1 = rb.highlowcontainer.getKeyAtIndex(pos1)
s2 = x2.highlowcontainer.getKeyAtIndex(pos2)
}
}
}
if pos1 == length1 {
rb.highlowcontainer.appendCopyMany(x2.highlowcontainer, pos2, length2)
}
}
// AndNot computes the difference between two bitmaps and stores the result in the current bitmap
func (rb *Bitmap) AndNot(x2 *Bitmap) {
pos1 := 0
pos2 := 0
intersectionsize := 0
length1 := rb.highlowcontainer.size()
length2 := x2.highlowcontainer.size()
main:
for {
if pos1 < length1 && pos2 < length2 {
s1 := rb.highlowcontainer.getKeyAtIndex(pos1)
s2 := x2.highlowcontainer.getKeyAtIndex(pos2)
for {
if s1 == s2 {
c1 := rb.highlowcontainer.getWritableContainerAtIndex(pos1)
c2 := x2.highlowcontainer.getContainerAtIndex(pos2)
diff := c1.iandNot(c2)
if diff.getCardinality() > 0 {
rb.highlowcontainer.replaceKeyAndContainerAtIndex(intersectionsize, s1, diff, false)
intersectionsize++
}
pos1++
pos2++
if (pos1 == length1) || (pos2 == length2) {
break main
}
s1 = rb.highlowcontainer.getKeyAtIndex(pos1)
s2 = x2.highlowcontainer.getKeyAtIndex(pos2)
} else if s1 < s2 {
c1 := rb.highlowcontainer.getContainerAtIndex(pos1)
mustCopyOnWrite := rb.highlowcontainer.needsCopyOnWrite(pos1)
rb.highlowcontainer.replaceKeyAndContainerAtIndex(intersectionsize, s1, c1, mustCopyOnWrite)
intersectionsize++
pos1++
if pos1 == length1 {
break main
}
s1 = rb.highlowcontainer.getKeyAtIndex(pos1)
} else { //s1 > s2
pos2 = x2.highlowcontainer.advanceUntil(s1, pos2)
if pos2 == length2 {
break main
}
s2 = x2.highlowcontainer.getKeyAtIndex(pos2)
}
}
} else {
break
}
}
// TODO:implement as a copy
for pos1 < length1 {
c1 := rb.highlowcontainer.getContainerAtIndex(pos1)
s1 := rb.highlowcontainer.getKeyAtIndex(pos1)
mustCopyOnWrite := rb.highlowcontainer.needsCopyOnWrite(pos1)
rb.highlowcontainer.replaceKeyAndContainerAtIndex(intersectionsize, s1, c1, mustCopyOnWrite)
intersectionsize++
pos1++
}
rb.highlowcontainer.resize(intersectionsize)
}
// Or computes the union between two bitmaps and returns the result
func Or(x1, x2 *Bitmap) *Bitmap {
answer := NewBitmap()
pos1 := 0
pos2 := 0
length1 := x1.highlowcontainer.size()
length2 := x2.highlowcontainer.size()
main:
for (pos1 < length1) && (pos2 < length2) {
s1 := x1.highlowcontainer.getKeyAtIndex(pos1)
s2 := x2.highlowcontainer.getKeyAtIndex(pos2)
for {
if s1 < s2 {
answer.highlowcontainer.appendCopy(x1.highlowcontainer, pos1)
pos1++
if pos1 == length1 {
break main
}
s1 = x1.highlowcontainer.getKeyAtIndex(pos1)
} else if s1 > s2 {
answer.highlowcontainer.appendCopy(x2.highlowcontainer, pos2)
pos2++
if pos2 == length2 {
break main
}
s2 = x2.highlowcontainer.getKeyAtIndex(pos2)
} else {
answer.highlowcontainer.appendContainer(s1, x1.highlowcontainer.getContainerAtIndex(pos1).or(x2.highlowcontainer.getContainerAtIndex(pos2)), false)
pos1++
pos2++
if (pos1 == length1) || (pos2 == length2) {
break main
}
s1 = x1.highlowcontainer.getKeyAtIndex(pos1)
s2 = x2.highlowcontainer.getKeyAtIndex(pos2)
}
}
}
if pos1 == length1 {
answer.highlowcontainer.appendCopyMany(x2.highlowcontainer, pos2, length2)
} else if pos2 == length2 {
answer.highlowcontainer.appendCopyMany(x1.highlowcontainer, pos1, length1)
}
return answer
}
// And computes the intersection between two bitmaps and returns the result
func And(x1, x2 *Bitmap) *Bitmap {
answer := NewBitmap()
pos1 := 0
pos2 := 0
length1 := x1.highlowcontainer.size()
length2 := x2.highlowcontainer.size()
main:
for pos1 < length1 && pos2 < length2 {
s1 := x1.highlowcontainer.getKeyAtIndex(pos1)
s2 := x2.highlowcontainer.getKeyAtIndex(pos2)
for {
if s1 == s2 {
C := x1.highlowcontainer.getContainerAtIndex(pos1)
C = C.and(x2.highlowcontainer.getContainerAtIndex(pos2))
if C.getCardinality() > 0 {
answer.highlowcontainer.appendContainer(s1, C, false)
}
pos1++
pos2++
if (pos1 == length1) || (pos2 == length2) {
break main
}
s1 = x1.highlowcontainer.getKeyAtIndex(pos1)
s2 = x2.highlowcontainer.getKeyAtIndex(pos2)
} else if s1 < s2 {
pos1 = x1.highlowcontainer.advanceUntil(s2, pos1)
if pos1 == length1 {
break main
}
s1 = x1.highlowcontainer.getKeyAtIndex(pos1)
} else { // s1 > s2
pos2 = x2.highlowcontainer.advanceUntil(s1, pos2)
if pos2 == length2 {
break main
}
s2 = x2.highlowcontainer.getKeyAtIndex(pos2)
}
}
}
return answer
}
// Xor computes the symmetric difference between two bitmaps and returns the result
func Xor(x1, x2 *Bitmap) *Bitmap {
answer := NewBitmap()
pos1 := 0
pos2 := 0
length1 := x1.highlowcontainer.size()
length2 := x2.highlowcontainer.size()
for {
if (pos1 < length1) && (pos2 < length2) {
s1 := x1.highlowcontainer.getKeyAtIndex(pos1)
s2 := x2.highlowcontainer.getKeyAtIndex(pos2)
if s1 < s2 {
answer.highlowcontainer.appendCopy(x1.highlowcontainer, pos1)
pos1++
} else if s1 > s2 {
answer.highlowcontainer.appendCopy(x2.highlowcontainer, pos2)
pos2++
} else {
c := x1.highlowcontainer.getContainerAtIndex(pos1).xor(x2.highlowcontainer.getContainerAtIndex(pos2))
if c.getCardinality() > 0 {
answer.highlowcontainer.appendContainer(s1, c, false)
}
pos1++
pos2++
}
} else {
break
}
}
if pos1 == length1 {
answer.highlowcontainer.appendCopyMany(x2.highlowcontainer, pos2, length2)
} else if pos2 == length2 {
answer.highlowcontainer.appendCopyMany(x1.highlowcontainer, pos1, length1)
}
return answer
}
// AndNot computes the difference between two bitmaps and returns the result
func AndNot(x1, x2 *Bitmap) *Bitmap {
answer := NewBitmap()
pos1 := 0
pos2 := 0
length1 := x1.highlowcontainer.size()
length2 := x2.highlowcontainer.size()
main:
for {
if pos1 < length1 && pos2 < length2 {
s1 := x1.highlowcontainer.getKeyAtIndex(pos1)
s2 := x2.highlowcontainer.getKeyAtIndex(pos2)
for {
if s1 < s2 {
answer.highlowcontainer.appendCopy(x1.highlowcontainer, pos1)
pos1++
if pos1 == length1 {
break main
}
s1 = x1.highlowcontainer.getKeyAtIndex(pos1)
} else if s1 == s2 {
c1 := x1.highlowcontainer.getContainerAtIndex(pos1)
c2 := x2.highlowcontainer.getContainerAtIndex(pos2)
diff := c1.andNot(c2)
if diff.getCardinality() > 0 {
answer.highlowcontainer.appendContainer(s1, diff, false)
}
pos1++
pos2++
if (pos1 == length1) || (pos2 == length2) {
break main
}
s1 = x1.highlowcontainer.getKeyAtIndex(pos1)
s2 = x2.highlowcontainer.getKeyAtIndex(pos2)
} else { //s1 > s2
pos2 = x2.highlowcontainer.advanceUntil(s1, pos2)
if pos2 == length2 {
break main
}
s2 = x2.highlowcontainer.getKeyAtIndex(pos2)
}
}
} else {
break
}
}
if pos2 == length2 {
answer.highlowcontainer.appendCopyMany(x1.highlowcontainer, pos1, length1)
}
return answer
}
// AddMany add all of the values in dat
func (rb *Bitmap) AddMany(dat []uint32) {
if len(dat) == 0 {
return
}
prev := dat[0]
idx, c := rb.addwithptr(prev)
for _, i := range dat[1:] {
if highbits(prev) == highbits(i) {
c = c.iaddReturnMinimized(lowbits(i))
rb.highlowcontainer.setContainerAtIndex(idx, c)
} else {
idx, c = rb.addwithptr(i)
}
prev = i
}
}
// BitmapOf generates a new bitmap filled with the specified integers
func BitmapOf(dat ...uint32) *Bitmap {
ans := NewBitmap()
ans.AddMany(dat)
return ans
}
// Flip negates the bits in the given range (i.e., [rangeStart,rangeEnd)), any integer present in this range and in the bitmap is removed,
// and any integer present in the range and not in the bitmap is added.
// The function uses 64-bit parameters even though a Bitmap stores 32-bit values because it is allowed and meaningful to use [0,uint64(0x100000000)) as a range
// while uint64(0x100000000) cannot be represented as a 32-bit value.
func (rb *Bitmap) Flip(rangeStart, rangeEnd uint64) {
if rangeEnd > MaxUint32+1 {
panic("rangeEnd > MaxUint32+1")
}
if rangeStart > MaxUint32+1 {
panic("rangeStart > MaxUint32+1")
}
if rangeStart >= rangeEnd {
return
}
hbStart := uint32(highbits(uint32(rangeStart)))
lbStart := uint32(lowbits(uint32(rangeStart)))
hbLast := uint32(highbits(uint32(rangeEnd - 1)))
lbLast := uint32(lowbits(uint32(rangeEnd - 1)))
2018-05-19 08:49:46 -04:00
var max uint32 = maxLowBit
for hb := hbStart; hb <= hbLast; hb++ {
var containerStart uint32
if hb == hbStart {
containerStart = uint32(lbStart)
}
containerLast := max
if hb == hbLast {
containerLast = uint32(lbLast)
}
i := rb.highlowcontainer.getIndex(uint16(hb))
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if i >= 0 {
c := rb.highlowcontainer.getWritableContainerAtIndex(i).inot(int(containerStart), int(containerLast)+1)
if c.getCardinality() > 0 {
rb.highlowcontainer.setContainerAtIndex(i, c)
} else {
rb.highlowcontainer.removeAtIndex(i)
}
} else { // *think* the range of ones must never be
// empty.
rb.highlowcontainer.insertNewKeyValueAt(-i-1, uint16(hb), rangeOfOnes(int(containerStart), int(containerLast)))
2018-05-19 08:49:46 -04:00
}
}
}
// FlipInt calls Flip after casting the parameters (convenience method)
func (rb *Bitmap) FlipInt(rangeStart, rangeEnd int) {
rb.Flip(uint64(rangeStart), uint64(rangeEnd))
}
// AddRange adds the integers in [rangeStart, rangeEnd) to the bitmap.
// The function uses 64-bit parameters even though a Bitmap stores 32-bit values because it is allowed and meaningful to use [0,uint64(0x100000000)) as a range
// while uint64(0x100000000) cannot be represented as a 32-bit value.
func (rb *Bitmap) AddRange(rangeStart, rangeEnd uint64) {
if rangeStart >= rangeEnd {
return
}
if rangeEnd-1 > MaxUint32 {
panic("rangeEnd-1 > MaxUint32")
}
hbStart := uint32(highbits(uint32(rangeStart)))
lbStart := uint32(lowbits(uint32(rangeStart)))
hbLast := uint32(highbits(uint32(rangeEnd - 1)))
lbLast := uint32(lowbits(uint32(rangeEnd - 1)))
var max uint32 = maxLowBit
for hb := hbStart; hb <= hbLast; hb++ {
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containerStart := uint32(0)
if hb == hbStart {
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containerStart = lbStart
}
containerLast := max
if hb == hbLast {
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containerLast = lbLast
}
i := rb.highlowcontainer.getIndex(uint16(hb))
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if i >= 0 {
c := rb.highlowcontainer.getWritableContainerAtIndex(i).iaddRange(int(containerStart), int(containerLast)+1)
rb.highlowcontainer.setContainerAtIndex(i, c)
} else { // *think* the range of ones must never be
// empty.
rb.highlowcontainer.insertNewKeyValueAt(-i-1, uint16(hb), rangeOfOnes(int(containerStart), int(containerLast)))
2018-05-19 08:49:46 -04:00
}
}
}
// RemoveRange removes the integers in [rangeStart, rangeEnd) from the bitmap.
// The function uses 64-bit parameters even though a Bitmap stores 32-bit values because it is allowed and meaningful to use [0,uint64(0x100000000)) as a range
// while uint64(0x100000000) cannot be represented as a 32-bit value.
func (rb *Bitmap) RemoveRange(rangeStart, rangeEnd uint64) {
if rangeStart >= rangeEnd {
return
}
if rangeEnd-1 > MaxUint32 {
// logically, we should assume that the user wants to
// remove all values from rangeStart to infinity
// see https://github.com/RoaringBitmap/roaring/issues/141
rangeEnd = uint64(0x100000000)
}
hbStart := uint32(highbits(uint32(rangeStart)))
lbStart := uint32(lowbits(uint32(rangeStart)))
hbLast := uint32(highbits(uint32(rangeEnd - 1)))
lbLast := uint32(lowbits(uint32(rangeEnd - 1)))
var max uint32 = maxLowBit
if hbStart == hbLast {
i := rb.highlowcontainer.getIndex(uint16(hbStart))
if i < 0 {
return
}
c := rb.highlowcontainer.getWritableContainerAtIndex(i).iremoveRange(int(lbStart), int(lbLast+1))
if c.getCardinality() > 0 {
rb.highlowcontainer.setContainerAtIndex(i, c)
} else {
rb.highlowcontainer.removeAtIndex(i)
}
return
}
ifirst := rb.highlowcontainer.getIndex(uint16(hbStart))
ilast := rb.highlowcontainer.getIndex(uint16(hbLast))
if ifirst >= 0 {
if lbStart != 0 {
c := rb.highlowcontainer.getWritableContainerAtIndex(ifirst).iremoveRange(int(lbStart), int(max+1))
if c.getCardinality() > 0 {
rb.highlowcontainer.setContainerAtIndex(ifirst, c)
ifirst++
}
}
} else {
ifirst = -ifirst - 1
}
if ilast >= 0 {
if lbLast != max {
c := rb.highlowcontainer.getWritableContainerAtIndex(ilast).iremoveRange(int(0), int(lbLast+1))
if c.getCardinality() > 0 {
rb.highlowcontainer.setContainerAtIndex(ilast, c)
} else {
ilast++
}
} else {
ilast++
}
} else {
ilast = -ilast - 1
}
rb.highlowcontainer.removeIndexRange(ifirst, ilast)
}
// Flip negates the bits in the given range (i.e., [rangeStart,rangeEnd)), any integer present in this range and in the bitmap is removed,
// and any integer present in the range and not in the bitmap is added, a new bitmap is returned leaving
// the current bitmap unchanged.
// The function uses 64-bit parameters even though a Bitmap stores 32-bit values because it is allowed and meaningful to use [0,uint64(0x100000000)) as a range
// while uint64(0x100000000) cannot be represented as a 32-bit value.
func Flip(bm *Bitmap, rangeStart, rangeEnd uint64) *Bitmap {
if rangeStart >= rangeEnd {
return bm.Clone()
}
if rangeStart > MaxUint32 {
panic("rangeStart > MaxUint32")
}
if rangeEnd-1 > MaxUint32 {
panic("rangeEnd-1 > MaxUint32")
}
answer := NewBitmap()
hbStart := uint32(highbits(uint32(rangeStart)))
lbStart := uint32(lowbits(uint32(rangeStart)))
hbLast := uint32(highbits(uint32(rangeEnd - 1)))
lbLast := uint32(lowbits(uint32(rangeEnd - 1)))
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// copy the containers before the active area
answer.highlowcontainer.appendCopiesUntil(bm.highlowcontainer, uint16(hbStart))
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var max uint32 = maxLowBit
for hb := hbStart; hb <= hbLast; hb++ {
var containerStart uint32
if hb == hbStart {
containerStart = uint32(lbStart)
}
containerLast := max
if hb == hbLast {
containerLast = uint32(lbLast)
}
i := bm.highlowcontainer.getIndex(uint16(hb))
j := answer.highlowcontainer.getIndex(uint16(hb))
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if i >= 0 {
c := bm.highlowcontainer.getContainerAtIndex(i).not(int(containerStart), int(containerLast)+1)
if c.getCardinality() > 0 {
answer.highlowcontainer.insertNewKeyValueAt(-j-1, uint16(hb), c)
2018-05-19 08:49:46 -04:00
}
} else { // *think* the range of ones must never be
// empty.
answer.highlowcontainer.insertNewKeyValueAt(-j-1, uint16(hb),
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rangeOfOnes(int(containerStart), int(containerLast)))
}
}
// copy the containers after the active area.
answer.highlowcontainer.appendCopiesAfter(bm.highlowcontainer, uint16(hbLast))
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return answer
}
// SetCopyOnWrite sets this bitmap to use copy-on-write so that copies are fast and memory conscious
// if the parameter is true, otherwise we leave the default where hard copies are made
// (copy-on-write requires extra care in a threaded context).
// Calling SetCopyOnWrite(true) on a bitmap created with FromBuffer is unsafe.
func (rb *Bitmap) SetCopyOnWrite(val bool) {
rb.highlowcontainer.copyOnWrite = val
}
// GetCopyOnWrite gets this bitmap's copy-on-write property
func (rb *Bitmap) GetCopyOnWrite() (val bool) {
return rb.highlowcontainer.copyOnWrite
}
// CloneCopyOnWriteContainers clones all containers which have
// needCopyOnWrite set to true.
// This can be used to make sure it is safe to munmap a []byte
// that the roaring array may still have a reference to, after
// calling FromBuffer.
// More generally this function is useful if you call FromBuffer
// to construct a bitmap with a backing array buf
// and then later discard the buf array. Note that you should call
// CloneCopyOnWriteContainers on all bitmaps that were derived
// from the 'FromBuffer' bitmap since they map have dependencies
// on the buf array as well.
func (rb *Bitmap) CloneCopyOnWriteContainers() {
rb.highlowcontainer.cloneCopyOnWriteContainers()
}
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// FlipInt calls Flip after casting the parameters (convenience method)
func FlipInt(bm *Bitmap, rangeStart, rangeEnd int) *Bitmap {
return Flip(bm, uint64(rangeStart), uint64(rangeEnd))
}
// Statistics provides details on the container types in use.
type Statistics struct {
Cardinality uint64
Containers uint64
ArrayContainers uint64
ArrayContainerBytes uint64
ArrayContainerValues uint64
BitmapContainers uint64
BitmapContainerBytes uint64
BitmapContainerValues uint64
RunContainers uint64
RunContainerBytes uint64
RunContainerValues uint64
}
// Stats returns details on container type usage in a Statistics struct.
func (rb *Bitmap) Stats() Statistics {
stats := Statistics{}
stats.Containers = uint64(len(rb.highlowcontainer.containers))
for _, c := range rb.highlowcontainer.containers {
stats.Cardinality += uint64(c.getCardinality())
switch c.(type) {
case *arrayContainer:
stats.ArrayContainers++
stats.ArrayContainerBytes += uint64(c.getSizeInBytes())
stats.ArrayContainerValues += uint64(c.getCardinality())
case *bitmapContainer:
stats.BitmapContainers++
stats.BitmapContainerBytes += uint64(c.getSizeInBytes())
stats.BitmapContainerValues += uint64(c.getCardinality())
case *runContainer16:
stats.RunContainers++
stats.RunContainerBytes += uint64(c.getSizeInBytes())
stats.RunContainerValues += uint64(c.getCardinality())
}
}
return stats
}