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How do I convert dates in a Pandas data frame to a 'date' data type?
... The pandas timestamp have both date and time. Do you mean convert it into python date object?
– waitingkuo
May 31 '13 at 8:42
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What does .SD stand for in data.table in R
...ng with it. What does it stand for? Why is there a preceding period (full stop). What is happening when I use it?
3 Answers...
Nullable Foreign Key bad practice?
Let's say you have a table Orders with a foreign key to a Customer Id. Now, suppose you want to add an Order without a Customer Id, (whether that should be possible is another question) you would have to make the foreign key NULL... Is that bad practice or would you rather work with a link table bet...
Check if a user has scrolled to the bottom
...stem (sort of like Facebook) where the content loads when the user scrolls to the bottom. I imagine the best way to do that is to find when the user is at the bottom of the page and run an ajax query to load more posts.
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Where to find “Microsoft.VisualStudio.TestTools.UnitTesting” missing dll?
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You have to add reference to
Microsoft.VisualStudio.QualityTools.UnitTestFramework.dll
It can be found at "C:\Program Files\Microsoft Visual Studio 10.0\Common7\IDE\PublicAssemblies\" directory (for VS2010 professional or above; ...
IEnumerable vs List - What to Use? How do they work?
I have some doubts over how Enumerators work, and LINQ. Consider these two simple selects:
10 Answers
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(413) Request Entity Too Large | uploadReadAheadSize
...7.5.
One of the service methods has an 'object' as argument and I'm trying to send a byte[] which contains a picture.
As long as the file size of this picture is less then approx. 48KB, all goes well. But if I'm trying to upload a larger picture, the WCF service returns an error: (413) Request Enti...
Difference between CouchDB and Couchbase
... some essential differences between CouchDB and Couchbase Server that need to be pointed out.
I will not write about the advantages of switching from CouchDB to the Couchbase Server because those are described pretty much everywhere (see The Future of CouchDB by Damien Katz or
Couchbase vs. Apache...
Working copy locked error in tortoise svn while committing
I'm using Tortoise SVN to update and commit changes to the repository in the server whenever I make changes to my working copy. But from a few days I'm not able to commit the changes and I get the following error whenever I try to commit.
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File being used by another process after using File.Create()
I'm trying to detect if a file exists at runtime, if not, create it. However I'm getting this error when I try to write to it:
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