A bitset class in Swift for fast and concise set operations over integers. Works under both Linux and MacOS. It is engineered to be really fast, on par with portable C/C++ implementations.
It can be orders of magnitude faster than an IndexSet:
$ git clone https://github.com/lemire/SwiftBitsetBenchmark.git
$ cd SwiftBitsetBenchmark
$ swift build -Xcc -march=native --configuration release
$ $(swift build --configuration release --show-bin-path)/SwiftBitsetBenchmark
testAddPerformance 10.693318 ms
testIndexSetAddPerformance 231.737616 ms
testCountPerformance 0.617098 ms
testIndexSetCountPerformance 0.007483 ms
testIteratorPerformance 5.503873 ms
testIndexSetIteratorPerformance 234.289692 ms
testIntersectionPerformance 3.157883 ms
testIndexSetIntersectionPerformance 2774.959423 ms
See https://github.com/lemire/SwiftBitsetBenchmark
Create a directory where you will create your application:
mkdir fun
cd fun
swift package init --type executableThen edit Package.swift so that it reads something like this:
import PackageDescription
let package = Package(
name: "fun",
dependencies: [
.package(url: "https://github.com/lemire/SwiftBitset.git", from: "0.3.2")
],
targets: [
.target(
name: "fun",
dependencies: ["Bitset"]),
]
)Edit main.swift (in Sources) so that it looks something like this :
import Bitset;
let b1 = Bitset (arrayLiteral: 1,4,10,1000,10000);
for i in b1 {
print(i)
}You can run your example as follows:
swift build -Xcc -march=native --configuration release
$(swift build --configuration release --show-bin-path)/funimport Bitset;
let b1 = Bitset ();
b1.add(10000) // can add one
b1.addMany(1,4,10,1000,10000); // can add many
let b2 = Bitset ();
b2.addMany(1,3,10,1000);
let bexpected = Bitset (1,3,4,10,1000,10000); // can init with list
b2.union(b1)
print(b2.count() == 6) // print true
print(b2 == bexpected) // print true
bexpected.intersection(b1)
print(b1 == bexpected) // print true
for i in b1 {
print(i)
}
// will print 1 4 10 1000 10000
b1.remove(4) // can remove values
let d1 = b1 & b2;// intersection
let d2 = b1 | b2;// union
let d3 = b1 - b2;// difference
let d4 = b1 ^ b2;// symmetric difference
b1 &= b2;// inplace intersection
b1 |= b2;// inplace union
b1 -= b2;// inplace difference
b1 ^= b2;// inplace symmetric differenceswift build -Xcc -march=native --configuration release
swift test # optionalTo dissamble a function...
swift build -Xcc -march=native --configuration release
lldb ./.build/release/Bitset.build/Bitset.swift.o
disassemble -n intersectionCountTo benchmark from the command line:
swift test -Xswiftc -Ounchecked -s BitsetTests.BitsetTests/testForEachPerformance
For interactive use:
$ swift build -Xcc -march=native --configuration release
$ swift -I .build/release -L .build/release -lBitsetDynamic
1> import Bitset
2> let b1 = Bitset ()
3> print(b1)$ swift package generate-xcodeproj
generated: ./Bitset.xcodeproj
$ open ./SwiftBitset.xcodeprojApache 2.0