如何使用if/and？[副本]

Question

我试着用带有“and”的if函数。它不起作用-有更好的方法或更好的命令吗？下面是我的代码示例：

        if measure >= 4.52 and <= 4.58:
            optimal += measure
            total += measure
            count += 1
        elif measure >= 4.50 and <= 4.60:
            allowed += measure
            total += measure
            count += 1
        else:
            faulty += measure
            total += measure
            count += 1

谢谢帮忙！

Answer 1

问题不在于if，而在于和。将if从图片中取出一秒钟：

>>> measure = 4.53
>>> measure >= 4.52 and <= 4.58
  File "<stdin>", line 1
    measure >= 4.52 and <= 4.58
                         ^
SyntaxError: invalid syntax

它无效，因为

>>> measure >= 4.52 and measure <= 4.58
True

现在，您有了一个有效的布尔语句（由和将另外两个布尔语句结合在一起产生），您可以在if语句中使用该语句：

>>> if measure >= 4.52 and measure <= 4.58:
...     print("success!")
... 
success!

如果要检查某个值是否介于其他两个值之间，则根本不需要和；您还可以将不等式运算符组合到一条语句中，如下所示：

>>> 4.52 <= measure <= 4.58
True

Answer 2

您需要在if条件下重复测量。像这样：

        if measure >= 4.52 and measure <= 4.58:
            optimal += measure
            total += measure
            count += 1
        elif measure >= 4.50 and measure <= 4.60:
            allowed += measure
            total += measure
            count += 1
        else:
            faulty += measure
            total += measure
            count += 1