python 整数比较确实很尴尬（看似简单）的错误
我有以下一段代码，它根本没有按照我期望的方式工作...
current_frame = 15 # just for showcasing purposes
g_ch = 7
if (current_frame != int(row[0])) and (int(row[1]) != g_ch):
current_frame = int(row[0])
print "curious================================="
print current_frame
print row
print current_frame, " != ", int(row[0]), ", ", current_frame != int(row[0])
print "========================================"
它针对任何特定情况进行打印：
curious=================================
15
['15', '1', 'more data'] 15 != 15 , False
========================================
显然，这甚至不应该输入 if 语句，因为相等性显示为 false。为什么会发生这种情况？
编辑：我也尝试过用 != 而不是“不是”，并得到了相同的结果。
I have the following piece of code which is not working the way I expect it to at all...
current_frame = 15 # just for showcasing purposes
g_ch = 7
if (current_frame != int(row[0])) and (int(row[1]) != g_ch):
current_frame = int(row[0])
print "curious================================="
print current_frame
print row
print current_frame, " != ", int(row[0]), ", ", current_frame != int(row[0])
print "========================================"
which prints for any specific case:
curious=================================
15
['15', '1', 'more data'] 15 != 15 , False
========================================
This should obviously never even enter the if statement, as the equality is showing false. Why is this happening?
edit: I have also tried this with != instead of 'is not', and gotten the same results.
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评论（3）
值比较是使用
!=运算符完成的，而不是使用is not来完成的，后者比较对象标识。除此之外，我认为这是一个缩进问题。
Value comparisons are done with the
!=operator, not withis not, which compares object identity.Apart from that, I think it's an indentation problem.
简而言之，您需要使用
==和!=，而不是is。is比较对象同一性，而不是相等性。In short, you need to use
==and!=, and notis.iscompares object identity, not equality.您可以在 if 内指定
current_frame = int(row[0])，这会更改布尔表达式的值。You assign
current_frame = int(row[0])inside the if, which changes the value of the boolean expression.