README
¶
partition
GO/golang package for partitioning slices, arrays and strings.
Introduction
I needed a solution for partitioning a slice. I searched for an existing package, and found the following StackOverflow question: https://stackoverflow.com/questions/30242567/in-go-how-can-i-partition-a-slice-array-string-of-any-type
This pointed to a package which only has an implementation that uses chans. That has to much overhead too my liking so I wrote this package, but added more options of using this package to add flexibility in using this package.
This package is fully unit tested and documented.
Usage
Download the package with the following command:
go get github.com/crosscode-nl/partition
Use the following import in your code to use the package.
import "github.com/crosscode-nl/partition"
Performance
The following benchmarks show that the partition.ToFunc function is the fastest to use.
BenchmarkToChan100-4 50000 25862 ns/op
BenchmarkToChan10-4 300000 4939 ns/op
BenchmarkToChan0-4 500000 2727 ns/op
BenchmarkToFunc100-4 5000000 230 ns/op
BenchmarkToFunc10-4 30000000 46.5 ns/op
BenchmarkToFunc0-4 100000000 14.6 ns/op
BenchmarkToHandler100-4 500000 3877 ns/op
BenchmarkToHandler10-4 1000000 1233 ns/op
BenchmarkToHandler0-4 3000000 478 ns/op
BenchmarkToIndices10-4 2000000 739 ns/op
BenchmarkToIndices100-4 500000 3241 ns/op
BenchmarkToIndices0-4 50000000 26.5 ns/op
Examples
partition.ToFunc
This func takes a func that receives all partitions one by one.
a := []int{1, 2, 3, 4, 5, 6, 7, 8, 9}
partition.ToFunc(len(a), 5, func(l int, h int) {
fmt.Printf("Part: %v\n", a[l:h])
})
// Output:
// Part: [1 2 3 4 5]
// Part: [6 7 8 9]
partition.ToChan
This func returns a chan that receives all partitions one by one.
a := []int{1, 2, 3, 4, 5, 6, 7, 8, 9}
for part := range partition.ToChan(len(a), 5) {
fmt.Printf("Part: %v\n", a[part.Low:part.High])
}
// Output:
// Part: [1 2 3 4 5]
// Part: [6 7 8 9]
partition.ToHandler
This func takes an implementation of the partition.Handler interface.
// Handler interface defines an interface for a partition handler that Partition accepts.
type Handler interface {
Handle(lowIndex int, highIndex int)
}
The example contains an implementation used by the unit tests partition.SliceHandler
a := []int{1, 2, 3, 4, 5, 6, 7, 8, 9}
s := partition.SliceHandler{}
partition.ToHandler(len(a), 5, &s)
for _, part := range s.Parts {
fmt.Printf("Part: %v\n", a[part.Low:part.High])
}
// Output:
// Part: [1 2 3 4 5]
// Part: [6 7 8 9]
partition.ToIndices
This func returns a slice with all partitions.
a := []int{1, 2, 3, 4, 5, 6, 7, 8, 9}
for _, part := range partition.ToIndices(len(a), 5) {
fmt.Printf("Part: %v\n", a[part.Low:part.High])
}
// Output:
// Part: [1 2 3 4 5]
// Part: [6 7 8 9]
License
MIT License
Copyright (c) 2019 CrossCode
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.
Documentation
¶
Overview ¶
Package partition contains methods to help partition slices. Benchmark results show that the ToFunc function is the fastest option available in this package. BenchmarkToChan100-4 300000 4166 ns/op BenchmarkToChan10-4 2000000 840 ns/op BenchmarkToChan0-4 3000000 435 ns/op BenchmarkToFunc100-4 10000000 197 ns/op BenchmarkToFunc10-4 50000000 24.9 ns/op BenchmarkToFunc0-4 500000000 3.05 ns/op BenchmarkToHandler100-4 3000000 590 ns/op BenchmarkToHandler10-4 10000000 127 ns/op BenchmarkToHandler0-4 50000000 38.8 ns/op BenchmarkToIndices10-4 20000000 90.0 ns/op BenchmarkToIndices100-4 3000000 504 ns/op BenchmarkToIndices0-4 300000000 4.98 ns/op
Index ¶
Examples ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func ToChan ¶
ToChan returns a chan that receives indices for all parts.
Example ¶
package main
import (
"fmt"
"github.com/crosscode-nl/partition"
)
func main() {
a := []int{1, 2, 3, 4, 5, 6, 7, 8, 9}
for part := range partition.ToChan(len(a), 5) {
fmt.Printf("Part: %v\n", a[part.Low:part.High])
}
}
Output: Part: [1 2 3 4 5] Part: [6 7 8 9]
func ToFunc ¶
func ToFunc(totalLength int, partitionLength int, hf HandleFunc)
ToFunc calls provided func per fragment
Example ¶
package main
import (
"fmt"
"github.com/crosscode-nl/partition"
)
func main() {
a := []int{1, 2, 3, 4, 5, 6, 7, 8, 9}
partition.ToFunc(len(a), 5, func(l int, h int) {
fmt.Printf("Part: %v\n", a[l:h])
})
}
Output: Part: [1 2 3 4 5] Part: [6 7 8 9]
func ToHandler ¶
ToHandler calls the handler for each part.
Example ¶
package main
import (
"fmt"
"github.com/crosscode-nl/partition"
)
func main() {
a := []int{1, 2, 3, 4, 5, 6, 7, 8, 9}
s := partition.SliceHandler{}
partition.ToHandler(len(a), 5, &s)
for _, part := range s.Parts {
fmt.Printf("Part: %v\n", a[part.Low:part.High])
}
}
Output: Part: [1 2 3 4 5] Part: [6 7 8 9]
Types ¶
type HandleFunc ¶
HandleFunc type defines the func that is used as a callback in ToFunc
type Handler ¶
Handler interface defines an interface for a partition handler that Partition accepts.
type Indices ¶
type Indices struct {
// Low contains the low index of part
Low int
// High contains the high index of part
High int
}
Indices contains a low and high index of a partition
func ToIndices ¶
ToIndices returns []Indices
Example ¶
package main
import (
"fmt"
"github.com/crosscode-nl/partition"
)
func main() {
a := []int{1, 2, 3, 4, 5, 6, 7, 8, 9}
for _, part := range partition.ToIndices(len(a), 5) {
fmt.Printf("Part: %v\n", a[part.Low:part.High])
}
}
Output: Part: [1 2 3 4 5] Part: [6 7 8 9]
type SliceHandler ¶
type SliceHandler struct {
Parts []Indices
}
SliceHandler is an implementation of partition.Handler and is a handler that is used internally and for tests and examples.
func (*SliceHandler) Handle ¶
func (h *SliceHandler) Handle(lowIndex int, highIndex int)
Handle implements handling a partition part.
Source Files