简单的python代码不会将字符串转换为浮点数

Question

我试图编写代码来显示从计算中得出一个高的球 但是无论我怎么键入，它总是在高度变量上说“ cannot convert string to float”

time = input("How long did the ball go up? in seconds\n")
time = float(time)

velocity = input("What was the initial velocity?\n")
velocity = float(velocity)

height = ("What was the initial height?\n")
height = float(height)

answer = (time ** 2 * -16) + (velocity * time) + height

print(answer)

  

ValueError：无法将字符串转换为float：'初始高度是多少？\ n'

为什么代码不想转换？

Answer 1

之所以会这样，是因为时间是string。您不能更改数据类型，但是可以强制转换它。相反，您应该做的是：

time = input("How long did the ball go up? in seconds\n")

velocity = input("What was the initial velocity?\n")

height = input("What was the initial height?\n")

answer = (float(time) ** 2 * -16) + (float(velocity) * float(time)) + float(height)

print(answer)