python - 格式化我的小数时遇到问题

Question

我需要我的输出保留 3 位小数

def main():

    n = eval(input("Enter the number of random steps: "))
    t = eval(input("Enter the number of trials: "))

    pos = 0
    totalPosition = 0
    totalSum = 0
    L = list()

    import random
    A = [-1, 1]

    for x in range(t):
        pos = 0
        for y in range(n):
            step = random.choice(A)
            pos += step


        totalPosition += abs(pos)
        totalSum += pos**2

    pos1 = totalPosition/t
    totalSum /= t
    totalSum = totalSum**0.5


    print("The average distance from the starting point is a %.3f", % pos1)
    print("The RMS distance from the starting point is %.3f", % totalSum)

main()

无论我尝试同时使用 '%' 字符还是 {0:.3f} .format(pos1) 方法，我都会不断收到语法错误。有人知道我哪里出错了吗？

谢谢!

Answer 1

你不需要 , 在打印函数中只需要 % 例如:

print("The RMS distance from the starting point is %.3f", % totalSum)
                                                        ^ remove this ,

喜欢:

print("The RMS distance from the starting point is %.3f" % totalSum)