Parse a string to float in Go (Golang)

strconv.ParseFloat() function can be used to parse a string representation of a float

https://golang.org/pkg/strconv/#ParseFloat

Below is the signature of the function

func ParseFloat(s string, bitSize int) (float64, error) 

Some points worth noting

• The first argument is the string representation of a float

• The second argument is the bitSize which specifies the precision. It is 32 for float32 and 64 for float64

• The return value will always be float64 but will be convertible to float32 without any change in its value.

Let’s see a working code

package main

import (
    "fmt"
    "strconv"
)

func main() {
    e1 := "1.3434"
    if s, err := strconv.ParseFloat(e1, 32); err == nil {
        fmt.Printf("%T, %v\n", s, s)
    }
    if s, err := strconv.ParseFloat(e1, 64); err == nil {
        fmt.Printf("%T, %v\n", s, s)
    }
}

Output

float64, 1.343400001525879
float64, 1.3434