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How to reorder data.table columns (without copying)
...mes(dt)[!(colnames(dt) %in% c("someCol"))]))
– hedgedandlevered
Aug 17 '16 at 16:18
6
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How can I create a Set of Sets in Python?
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Python's complaining because the inner set objects are mutable and thus not hashable. The solution is to use frozenset for the inner sets, to indicate that you have no intention of modifying them.
share
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Git and Mercurial - Compare and Contrast
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Disclaimer: I use Git, follow Git development on git mailing list, and even contribute a bit to Git (gitweb mainly). I know Mercurial from documentation and some from discussion on #revctrl IRC channel on FreeNode.
Thanks to all people on on #mercurial IRC channel who provided help about Mer...
Django - Circular model import issue
... this works I'd very much appreciate it. I have two applications, Accounts and Theme... here is my settings list:
4 Answers...
What is difference between width, innerWidth and outerWidth, height, innerHeight and outerHeight in
... to see what is the difference, but they display me same results for width and height.
6 Answers
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Hyphen, underscore, or camelCase as word delimiter in URIs?
...ed API for an intranet app. I realize it's a pretty small concern in the grand scheme of things, but: should I use hyphens, underscores, or camelCase to delimit words in the URIs?
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How do I switch to another subversion branch in Intellij?
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Right because here you are "updating" your sandbox to a new branch.
– Shaun F
Oct 21 '09 at 0:47
52
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MySQL/SQL: Group by date only on a Datetime column
...able GROUP BY DATE(a_table.mydate);
Or you can GROUP BY the alias as @orlandu63 suggested:
SELECT SUM(foo), DATE(mydate) DateOnly FROM a_table GROUP BY DateOnly;
Though I don't think it'll make any difference to performance, it is a little clearer.
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Spring classpath prefix difference
...es under conf folders in all your jars on the classpath will be picked up and joined into one big application context.
In contrast, classpath:conf/appContext.xml will load only one such file... the first one found on your classpath.
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Possible Loss of Fraction
... postfix: "",
imageUploader: {
brandingHtml: "Powered by \u003ca href=\"https://imgur.com/\"\u003e\u003csvg class=\"svg-icon\" width=\"50\" height=\"18\" viewBox=\"0 0 50 18\" fill=\"none\" xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9....