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Pandas aggregate count distinct
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That's it. pd.Series.nunique is what I couldn't find, well, couldn't get to work correctly. Pretty obvious in hindsight. Thanks!
– dave
Sep 1 '13 at 3:36
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How to create EditText with cross(x) button at end of it?
Is there any widget like EditText which contains a cross button, or is there any property for EditText by which it is created automatically? I want the cross button to delete whatever text written in EditText .
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What does android:layout_weight mean?
...ews. E.g. you have a MapView and a table which should show some additional information to the map. The map should use 3/4 of the screen and table should use 1/4 of the screen. Then you will set the layout_weight of the map to 3 and the layout_weight of the table to 1.
To get it work you also have ...
Use C++ with Cocoa Instead of Objective-C?
...applications that use C++ and the Cocoa frameworks because Apple is not making Carbon 64-bit capable. C++ seems to be pretty vanilla in its implementation on Linux and Windows but on Mac OS X it seems like additional Apple specific pieces of code are required (like an Obj-C wrapper). It also seems t...
Best design for a changelog / auditing database table? [closed]
I need to create a database table to store different change log/auditing
(when something was added, deleted, modified, etc). I don't need to store particularly detailed info, so I was thinking something along the lines of:
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How do I find the most recent git commit that modified a file?
I want to find the most recent commit that modified a source file.
6 Answers
6
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How to use if statements in underscore.js templates?
I'm using the underscore.js templating function and have done a template like this:
8 Answers
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Cannot push to Heroku because key fingerprint
I am new to Rails, and I was trying to deploy a very simple app to Heroku. This is the second app that I deploy, and the first one I was able to do it just fine. However I am having some issues with this one. Whenever I " git push heroku master ", I get this error:
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Postgresql GROUP_CONCAT equivalent?
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This is probably a good starting point (version 8.4+ only):
SELECT id_field, array_agg(value_field1), array_agg(value_field2)
FROM data_table
GROUP BY id_field
array_agg returns an array, but you can CAST that to text and edit as needed (see clarifica...
What's the difference between belongs_to and has_one?
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They essentially do the same thing, the only difference is what side of the relationship you are on. If a User has a Profile, then in the User class you'd have has_one :profile and in the Profile class you'd have belongs_to :user. To determine who "has" th...