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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
})
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How to specify in crontab by what user to run script? [closed]
...tab jobs that run under root, but that gives me some problems. For example all folders created in process of that cron job are under user root and group root.
How can i make it to run under user www-data and group www-data so when i run scripts from my website i can manipulate those folders and fil...
How to check if a String contains only ASCII?
The call Character.isLetter(c) returns true if the character is a letter. But is there a way to quickly find if a String only contains the base characters of ASCII?
...
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...
'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...
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...
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...
When to use .First and when to use .FirstOrDefault with LINQ?
I've searched around and haven't really found a clear answer as to when you'd want to use .First and when you'd want to use .FirstOrDefault with LINQ.
...
What does it mean to inflate a view from an xml file?
...evelopment and keep coming across references to Inflating views from a layout xml file. I googled and searched the development guide but still wasn't able to pick up a sense for what it means. If someone could provide a very simple example, it'd be much appreciated.
...