int16数字加上golang中的float64

Question

I want to do a simple thing:

func (this *ScoreProvider) getScore()(res float64) {
    var score1 int16 = 500
    var score2 int16 = 400
    var score3 int16 = 300
    var score4 int16 = 200
    res = score1 * 0.25 + score2 * 0.25 + score3 * 0.25 + score4 * 0.25

    return
}

But this reports an error:

can not use score1 * 0 + score2 * 0 + score3 * 0 + score4 * 0 (type int16) as type float64 in assignment

How can I do this right?

Answer 1

Your constants (0.25) are being truncated to intergers (0).

Two ways to solve:

cast the score1 etc variables to float32:

var score1 int16 = 500
var score2 int16 = 400
var score3 int16 = 300
var score4 int16 = 200
res := float32(score1)*0.25 + float32(score2)*0.25 + float32(score3)*0.25 + float32(score4)*0.25

fmt.Println("Score", res)

or more sensible, instead of declaring them as int16 declare them as float32 to begin with:

var score1a float32 = 500
var score2a float32 = 400
var score3a float32 = 300
var score4a float32 = 200
res2 := score1a * 0.25 + score2a * 0.25 + score3a * 0.25 + score4a * 0.25

fmt.Println("Result 1", res)
fmt.Println("Result 2", res2)

On the Go Playground