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How to rename a single column in a data.frame?
I know if I have a data frame with more than 1 column, I can use
20 Answers
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Is null check needed before calling instanceof?
... was part of Java 1.0, released almost 20 years ago. Changing the behavior now in a way that would break existing code is unlikely, absent some benefit that outweighs that huge cost. Twenty years ago, maybe there could have been arguments for returning true iff the argument could be cast, or throwin...
How to make git mark a deleted and a new file as a file move?
...tructure.
Run git add -A .
Run git status to verify that the "new file" is now a "renamed" file
If git status still shows "new file" and not "renamed" you need to follow Hank Gay’s advice and do the move and modify in two separate commits.
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SQL query for today's date minus two months
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If you use MySQL this would become: MyDate < DATE_ADD(NOW(), INTERVAL -2 MONTH)
– Stefan
Feb 27 '14 at 15:51
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When should you NOT use a Rules Engine? [closed]
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Don't know if that's what you'd call it. What changes by using that name? Nothing that I can see...
– duffymo
Nov 12 '13 at 0:21
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Convert array to JSON
...] which holds a few integers.
I've added a few values to the array, but I now need to send this array to a page via jQuery's .get method. How can I convert it to a JSON object for sending?
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Save classifier to disk in scikit-learn
...digits.data, digits.target)
0.9526989426822482
Edit: in Python 3.8+ it's now possible to use pickle for efficient pickling of object with large numerical arrays as attributes if you use pickle protocol 5 (which is not the default).
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Partial Commits with Subversion
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Tortoise SVN 1.8 now supports this with it's "Restore after commit" feature. This allow you to make edits to a file, with all of the edits being undone after the commit
Per the documentation:
To commit only the parts of the file that rel...
Is there a “null coalescing” operator in JavaScript?
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Update
JavaScript now supports the nullish coalescing operator (??). It returns its right-hand-side operand when its left-hand-side operand is null or undefined, and otherwise returns its left-hand-side operand.
Please check compatibility be...
Import existing source code to GitHub
...ly why. If you create your github repo with a readme.md, you are actually now behind what you're trying to make your origin.
– user559633
Oct 31 '12 at 16:35
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