Golang中的固定cos数学函数是否有解决方案

I am trying to use cos function from math API in golang, but for some reason the function is returning an incorrect value. Is there a known solution for this problem?

Code:

    fmt.Println("cos(pi/2):", math.Cos(math.Pi / 2))
    fmt.Println("sen(pi/2):", math.Sin(math.Pi / 2))

Output:

cos(pi/2): 6.123233995736757e-17

sen(pi/2): 1

The cosine of pi / 2 is zero.

What you're seeing is just a slight floating point inaccuracy. It's correctly returning "almost zero".

See: What Every Computer Scientist Should Know About Floating-Point Arithmetic.