# Golang : Arithmetic operation with numerical slices or arrays example

Tags : golang mathematics arithmetic slices-arrays

Got an email from a new comer to Golang from South Africa, he or she wanted to know how to perform simple operations like arithmetic on numerical slices. There is a package - GoNum - that can do a better job for these kind of problems ... which I reckon is more efficient for mathematical calculations than using Golang's standard slices. However, there is no harm to use slices if all you wanted is to perform some simple operations like plus, minus, multiplication or division on slices or array.

Below is an example of how to use slices for arithmetic operations:

```
package main
import (
"fmt"
)
func main() {
a := []int{1, 2, 3, 4}
fmt.Println("Original : ", a)
// a * 2
for i, _ := range a {
a[i] = a[i] * 2
}
fmt.Println("a * 2 : ", a)
// a + 10
for i, _ := range a {
a[i] = a[i] + 10
}
fmt.Println("a + 10 : ", a)
b := []int{5, 6, 7, 8}
fmt.Println("b : ", b)
lengthOfA := len(a)
// will cause non-constant array bound lengthOfA error
//c := [lengthOfA]int{}
// if c size is constant, it is ok to hardcode with size of 4 (hand counted)
// c := [4]int{}
// or to make your program more robust
// figure out the slice c's length during runtime with length of a slice
c := make([]int, lengthOfA)
// a + b
// FOR a slice to plus b slice, the size or number of elements in both slices must be the same!
for i, _ := range a {
c[i] = a[i] + b[i]
}
fmt.Printf("a + b : %v + %v = %v \n", a, b, c)
d := make([]int, lengthOfA)
// a * b
for i, _ := range a {
d[i] = a[i] * b[i]
}
fmt.Printf("a * b : %v * %v = %v \n", a, b, d)
// use float64 instead of int type for division
e := make([]float64, lengthOfA)
// a / b
for i, _ := range a {
e[i] = float64(a[i]) / float64(b[i])
}
fmt.Printf("a / b : %v * %v = %v \n", a, b, e)
f := make([]int, lengthOfA)
// a - b
for i, _ := range a {
f[i] = a[i] - b[i]
}
fmt.Printf("a - b : %v * %v = %v \n", a, b, f)
}
```

Output:

Original : [1 2 3 4]

a * 2 : [2 4 6 8]

a + 10 : [12 14 16 18]

b : [5 6 7 8]

a + b : [12 14 16 18] + [5 6 7 8] = [17 20 23 26]

a * b : [12 14 16 18] * [5 6 7 8] = [60 84 112 144]

a / b : [12 14 16 18] * [5 6 7 8] = [2.4 2.3333333333333335 2.2857142857142856 2.25]

a - b : [12 14 16 18] * [5 6 7 8] = [7 8 9 10]

**References:**

https://socketloop.com/tutorials/golang-combine-slices-of-complex-numbers-and-operation-example

https://www.socketloop.com/tutorials/golang-squaring-elements-in-array

#### See also : Golang : Combine slices of complex numbers and operation example

Tags : golang mathematics arithmetic slices-arrays

##### 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

771 Golang : How to check if a string with spaces in between is numeric?

924 Golang : Use NLP to get sentences for each paragraph example

742 Java : Random alphabets, alpha-numeric or numbers only string generator

+2k Golang : How to validate ISBN?

+3.4k Golang : Error reading timestamp with GORM or SQL driver

+10.4k Golang : Get executable name behind process ID example

+12.2k Golang : Get local IP and MAC address

+2.9k Golang : Use regular expression to get all upper case or lower case characters example

+3.8k Golang : Verify Linux user password again before executing a program example

+2.7k Golang : Validate credit card example

+4.6k Golang : How to check if a file is hidden?

641 Java : Human readable password generator