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In Python how should I test if a variable is None, True or False
...
a = 'foo' if a: print 'its true' a is not actually TRUE, it's just not none
– wesm
Apr 3 '15 at 21:06
...
pandas GroupBy columns with NaN (missing) values
...n the Missing Data section of the docs:
NA groups in GroupBy are automatically excluded. This behavior is consistent with R, for example.
One workaround is to use a placeholder before doing the groupby (e.g. -1):
In [11]: df.fillna(-1)
Out[11]:
a b
0 1 4
1 2 -1
2 3 6
In [12]: df.fil...
How to sort in mongoose?
...t:{
date_added: -1 //Sort by Date Added DESC
}
},
function(err,allNews){
socket.emit('news-load', allNews); // Do something with the array of 10 objects
})
share
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improve this answ...
'UserControl' constructor with parameters in C#
Call me crazy, but I'm the type of guy that likes constructors with parameters (if needed), as opposed to a constructor with no parameters followed by setting properties. My thought process: if the properties are required to actually construct the object, they should go in the constructor. I get two...
AngularJS : Prevent error $digest already in progress when calling $scope.$apply()
I'm finding that I need to update my page to my scope manually more and more since building an application in angular.
28 A...
What are the differences between utf8_general_ci and utf8_unicode_ci? [duplicate]
...tf8_unicode_ci uses the standard Unicode Collation Algorithm, supports so called expansions and ligatures, for example:
German letter ß (U+00DF LETTER SHARP S) is sorted near "ss"
Letter Π(U+0152 LATIN CAPITAL LIGATURE OE) is sorted near "OE".
utf8_general_ci does not support expansions/liga...
How to read all files in a folder from Java?
How to read all the files in a folder through Java?
31 Answers
31
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编程基础与事件状态 08：独立完成专注与休息循环 · App Inventor 2 中文网
... 实例名
组件
本课配置
标签_标题
标签
Width=Fill parent；FontSize=24；TextColor=#183153；Text=专注学习 · 第 8课
垂直布局_专注
垂直布局
Width=Fill parent；Visible=True
按...
Does Go have “if x in” construct similar to Python?
...ion without separate methods for every single type
– Allen
May 13 '15 at 4:33
29
It could be done...
How to remove convexity defects in a Sudoku square?
...surements[
ColorNegate@Binarize[srcAdjusted], {"ConvexArea", "Mask"}][[All,
2]];
largestComponent = Image[SortBy[components, First][[-1, 2]]]
By filling this image, I get a mask for the sudoku grid:
mask = FillingTransform[largestComponent]
Now, I can use a 2nd order derivative fil...