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Python `if x is not None` or `if not x is None`?
I've always thought of the if not x is None version to be more clear, but Google's style guide and PEP-8 both use if x is not None . Is there any minor performance difference (I'm assuming not), and is there any case where one really doesn't fit (making the other a clear winner for my convent...
It is more efficient to use if-return-return or if-else-return?
Suppose I have an if statement with a return . From the efficiency perspective, should I use
8 Answers
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水果vs蔬菜智能分类器 - EdgeML图像识别项目 · App Inventor 2 中文网
...目实现步骤
第一步：了解 Personal Image Classifier (PIC)
PIC扩展的主要功能：
与传统机器学习的区别：
第二步：使用 PIC 训练自定义模型
1. 数...
SQL: IF clause within WHERE clause
Is it possible to use an IF clause within a WHERE clause in MS SQL?
14 Answers
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How can I determine the direction of a jQuery scroll event?
...= 0;
$(window).scroll(function(event){
var st = $(this).scrollTop();
if (st > lastScrollTop){
// downscroll code
} else {
// upscroll code
}
lastScrollTop = st;
});
share
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How can I safely create a nested directory?
What is the most elegant way to check if the directory a file is going to be written to exists, and if not, create the directory using Python? Here is what I tried:
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Checking if an object is null in C#
I would like to prevent further processing on an object if it is null.
17 Answers
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How to drop a table if it exists?
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Is it correct to do the following?
IF EXISTS(SELECT *
FROM dbo.Scores)
DROP TABLE dbo.Scores
No. That will drop the table only if it contains any rows (and will raise an error if the table does not exist).
Instead, for a permanent table you ...
#ifdef vs #if - which is better/safer as a method for enabling/disabling compilation of particular s
...ter of style, but there's a bit of a divide in our dev team and I wondered if anyone else had any ideas on the matter...
19...
Short form for Java if statement
I know there is a way for writing a Java if statement in short form.
15 Answers
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