Golang : Create matrix with Gonum Matrix package example
Here is an example of how to create and display matrix properly in Golang with Gonum package. Nothing special in this tutorial, will write another tutorial on how to find the matrix determinants and performing matrix calculations later on.
Here you go!
package main
import (
"fmt"
"github.com/gonum/matrix/mat64"
)
func main() {
m := mat64.NewDense(3, 5, nil)
// fill in m with some elements
for i := 0; i < 3; i++ {
m.Set(i, i, 99)
}
// wrong way to print matrix
fmt.Println("m : ", m)
// proper way
// refer to https://godoc.org/github.com/gonum/matrix/mat64#Excerpt
fmt.Printf("m :\n%v\n\n", mat64.Formatted(m, mat64.Prefix(" "), mat64.Excerpt(2)))
// print all m elements
fmt.Printf("m :\n%v\n\n", mat64.Formatted(m, mat64.Prefix(""), mat64.Excerpt(0)))
data := []float64{1, 2, 3}
m2 := mat64.NewDense(3, 1, data)
// print all m2 elements
fmt.Printf("m2 :\n%v\n\n", mat64.Formatted(m2, mat64.Prefix(""), mat64.Excerpt(0)))
// to build this matrix
// ⎡1 2 3⎤
// ⎢4 5 6⎥
// ⎣7 8 9⎦
// use SetRow or SetCol
m3 := mat64.NewDense(3, 3, nil)
m3.SetRow(0, data)
data2 := []float64{4, 5, 6}
m3.SetRow(1, data2)
data3 := []float64{7, 8, 9}
m3.SetRow(2, data3)
// print all m3 elements
fmt.Printf("m3 :\n%v\n\n", mat64.Formatted(m3, mat64.Prefix(""), mat64.Excerpt(0)))
// get transpose with m3.T()
fmt.Printf("m3 transpose :\n%v\n\n", mat64.Formatted(m3.T(), mat64.Prefix(""), mat64.Excerpt(0)))
}
Output:
m : &{{3 5 5 [99 0 0 0 0 0 99 0 0 0 0 0 99 0 0]} 3 5}
m :
Dims(3, 5)
⎡99 0 ... ... 0 0⎤
⎢ 0 99 0 0⎥
⎣ 0 0 ... ... 0 0⎦
m :
⎡99 0 0 0 0⎤
⎢ 0 99 0 0 0⎥
⎣ 0 0 99 0 0⎦
m2 :
⎡1⎤
⎢2⎥
⎣3⎦
m3 :
⎡1 2 3⎤
⎢4 5 6⎥
⎣7 8 9⎦
m3 transpose :
⎡1 4 7⎤
⎢2 5 8⎥
⎣3 6 9⎦
References:
https://godoc.org/github.com/gonum/matrix/mat64#Dense.SetRow
By Adam Ng
IF you gain some knowledge or the information here solved your programming problem. Please consider donating to the less fortunate or some charities that you like. Apart from donation, planting trees, volunteering or reducing your carbon footprint will be great too.
Advertisement
Tutorials
+32.9k Golang : Integer is between a range
+10.6k Golang : convert(cast) float to string
+6.3k Android Studio : AlertDialog to get user attention example
+7k Golang : Qt splash screen with delay example
+5k Fix ERROR 2003 (HY000): Can't connect to MySQL server on 'IP address' (111)
+16.5k Golang : How to log each HTTP request to your web server?
+6.9k Golang Hello World Example
+12.1k Golang : Generate Code128 barcode
+17.3k Golang : Padding data for encryption and un-padding data for decryption
+16.1k Golang : Multi threading or run two processes or more example
+4.3k Golang : The Tao of importing package
+28.3k Golang : Get and Set User-Agent examples