How to find variance in golang
The implementation method of finding variance in golang: 1. Reference the "github.com/grd/statistics" package; 2. Use the "data := statistics.Int64{1, 2, 3, 4, 5}" method Define the array; 3. Calculate the variance through the "variance := statistics.Variance(&data)" method.
The operating environment of this tutorial: Windows 10 system, GO version 1.18, Dell G3 computer.
How to find the variance in golang?
Golang Variance Algorithm
Quote "github.com/grd/statistics" package
func main() { //定义数组 data := statistics.Int64{1, 2, 3, 4, 5} //方差计算 variance := statistics.Variance(&data) //输出结果(2.5) fmt.Println(variance)
Related extensions:
When importing a package, import is a relative file path relative to src.
Several ways to import:
Click operation
Sometimes you will see the following ways to import packages:
import( . "fmt" )
The meaning of this point operation is that after the package is imported, when you call the function of this package, you can omit the prefixed package name, which is what you called earlier:
fmt.Println( "我爱北京天安门" )
can be omitted Written as:
Println( "我爱北京天安门" )
Alias operation
As the name suggests, the package can be named another name that is easy to remember:
import( f "fmt" )
Alias operation call When wrapping a function, the prefix becomes the rename prefix, that is:
f.Println( "我爱北京天安门" )
Underscore operation
This operation is often an operator that is confusing to many people, please see The following import
import ( “database/sql” _ “github.com/ziutek/mymysql/godrv” )
underline "_" operation actually just introduces the package. When a package is imported, all its init() functions will be executed, but sometimes you don't really need to use these packages, you just want its init() functions to be executed. At this time, you can use the "_" operation to reference the package. Even if you use the "_" operation to reference a package, you cannot call the exported functions in the package through the package name, but just to simply call its init() function.
The go language import keyword imports not a real package, but the path of a folder. If the package of the library source code file is inconsistent with the name of the directory where it is located, write the path to the folder when importing.
If the last level of the two imported packages is the same, a conflict will occur. The conflict resolution method is: alias operation.
Recommended learning: "go video tutorial"
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