catalogue
- preface
- The specific implementation steps are as follows
- 1. import and storage
- 2. assemble data and sort (scheme I)
- 3. assemble data and sort (scheme II)
- summary
preface
At present, we have received a demand for recommended data. We need to randomly sort the data obtained in the database and return it to the user. After considering, there are two ways to use it. One is through the database order by Rand (), and the other is the code processing required in this article
The specific implementation steps are as follows
1. import and storage
The codes are as follows:
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import ( "fmt" "math/rand" "time") |
2. assemble data and sort (scheme I)
The codes are as follows:
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type CategoryEntity struct { Grouponid Int64 // group ID Merchandiseid Int64 // product ID Categoryid Int64 // category ID Categorytitle string // category name}func main() { data := make([]CategoryEntity, 10) Data[0] = categoryentity{grouponid: 0, merchandiseid: 1117891, categoryid: 726, categorytitle: "vegetable"} Data[1] = categoryentity{grouponid: 1, merchandiseid: 1110162, categoryid: 1505, categorytitle: "seasoning"} Data[2] = categoryentity{grouponid: 2, merchandiseid: 1117822, categoryid: 746, categorytitle: "fruit"} Data[3] = categoryentity{grouponid: 3, merchandiseid: 1115770, categoryid: 1408, categorytitle: "personal care"} Data[4] = categoryentity{grouponid: 4, merchandiseid: 1116528, categoryid: 732, categorytitle: "meat"} Data[5] = categoryentity{grouponid: 5, merchandiseid: 1116526, categoryid: 727, categorytitle: "snack food"} Data[6] = categoryentity{grouponid: 6, merchandiseid: 1117188, categoryid: 728, categorytitle: "grain and oil seasoning"} Data[7] = categoryentity{grouponid: 7, merchandiseid: 1117379, categoryid: 726, categorytitle: "vegetable"} Data[8] = categoryentity{grouponid: 8, merchandiseid: 1118166, categoryid: 1005, categorytitle: "home department store"} Data[9] = categoryentity{grouponid: 9, merchandiseid: 1117377, categoryid: 746, categorytitle: "fruit"} fmt. Println ("before random:", data) //If rand Seed (seed Int64), the random number will be the same every time rand.Seed(time.Now().Unix()) //Rand Shuffle, randomize slices and return rand.Shuffle(len(data), func(i, j int) { data[i], data[j] = data[j], data[i] }) fmt. Println ("after random:", data)} |
3. assemble data and sort (scheme II)
The codes are as follows:
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type CategoryEntity struct { Grouponid Int64 // group ID Merchandiseid Int64 // product ID Categoryid Int64 // category ID Categorytitle string // category name}func main() { data := make([]CategoryEntity, 10) Data[0] = categoryentity{grouponid: 0, merchandiseid: 1117891, categoryid: 726, categorytitle: "vegetable"} Data[1] = categoryentity{grouponid: 1, merchandiseid: 1110162, categoryid: 1505, categorytitle: "seasoning"} Data[2] = categoryentity{grouponid: 2, merchandiseid: 1117822, categoryid: 746, categorytitle: "fruit"} Data[3] = categoryentity{grouponid: 3, merchandiseid: 1115770, categoryid: 1408, categorytitle: "personal care"} Data[4] = categoryentity{grouponid: 4, merchandiseid: 1116528, categoryid: 732, categorytitle: "meat"} Data[5] = categoryentity{grouponid: 5, merchandiseid: 1116526, categoryid: 727, categorytitle: "snack food"} Data[6] = categoryentity{grouponid: 6, merchandiseid: 1117188, categoryid: 728, categorytitle: "grain and oil seasoning"} Data[7] = categoryentity{grouponid: 7, merchandiseid: 1117379, categoryid: 726, categorytitle: "vegetable"} Data[8] = categoryentity{grouponid: 8, merchandiseid: 1118166, categoryid: 1005, categorytitle: "home department store"} Data[9] = categoryentity{grouponid: 9, merchandiseid: 1117377, categoryid: 746, categorytitle: "fruit"} fmt. Println ("before random:", data) //If rand Seed (seed Int64), the random number will be the same every time rand.Seed(time.Now().Unix()) length := len(data) for i := 0; i < length; i++ { exchange(data, rand.Intn(length), i) } fmt. Println ("after random:", data)}//Exchange datafunc exchange(data []CategoryEntity, i, j int) { data[i], data[j] = data[j], data[i]} |
summary
The whole is simple, but there are two points to note:
1: How to use Rand in golang. If Rand is not used Seed (seed Int64), the random number will be the same every time
2: The first scheme adopts rand Shuffle+ an anonymous function that randomizes slices and returns them.
3: Scheme 2 uses the unique array exchange method of golang:
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func exchange(data []CategoryEntity, i, j int) { data[i], data[j] = data[j], data[i]} |
This is the end of this article about the implementation of random sorting of golang arrays. For more information about random sorting of golang arrays, please search previous articles on developeppaper or continue to browse the following articles. I hope you will support developeppaper in the future!