python - 对于列表中的索引

Question

我正在努力寻找如何将减法的答案简化为小数点后两位。将 Enter 和 Leave 这两个列表相减，这样我就可以得到汽车从 A 点到 B 点所需的时间。

Enter=[7.12,
       7.15,
       7.24,
       7.45,
       7.28,
       7.31,
       7.18,
       7.25,
       7.33,
       7.38]

Leave=[7.56,
       7.24,
       7.48,
       7.52,
       7.45,
       7.57,
       7.22,
       7.31,
       7.37,
       7.41]

Timestaken=[]

for enter_data, leave_data in zip(Enter, Leave):
    Timestaken.append(leave_data-enter_data)

print (Timestaken)

for index in Timestaken:
    Timestaken[index]="%.2f" % Timestaken[index]

print(Timestaken)

当我在 IDLE 中运行它时，我收到以下信息:

>>> 
[0.4399999999999995, 0.08999999999999986, 0.2400000000000002, 0.0699999999999994, 0.16999999999999993, 0.2600000000000007, 0.040000000000000036, 0.05999999999999961, 0.040000000000000036, 0.03000000000000025]
Traceback (most recent call last):
  File "M:\Task 2 Testing.py", line 46, in <module>
    Timestaken[index]="%.2f" % Timestaken[index]
TypeError: list indices must be integers, not float

我需要这方面的帮助:

for index in Timestaken:
    Timestaken[index]="%.2f" % Timestaken[index]

Answer 1

这应该有效:

for value in Timestaken:
    print("%.2f" % value)