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How do you delete a column by name in data.table?
...hough data.table is gradually moving away from using this argument so it's now discouraged where you can avoid it; showing here so you know the option exists in case you really do need it:
# Method 5a (like Method 3)
df3[, !"foo", with=FALSE]
# Method 5b (like Method 4)
df3[, !grep("^foo$", names(...
HTML encoding issues - “” character showing up instead of “ ”
...he HTML itself, which is always a highly dodgy business.
Well anyway, for now you can add one of the following to your document's <head> and see if that makes it look right in the browser:
for HTML4: <meta http-equiv="Content-Type" content="text/html;charset=utf-8" />
for HTML5: <m...
__proto__ VS. prototype in JavaScript
...s: "This will work if f.__proto__ = g where g is the base class." I don't know if this has some meaning i don't understand, but if you were to add the properties and methods in that way, then when you used the new keyword to create an instance, the properties and methods wouldn't be copied over.
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Repairing Postgresql after upgrading to OSX 10.7 Lion
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It's a PATH issue. Mac OSX Lion includes Postgresql in the system now. If you do a which psql you'll likely see usr/bin/psql instead of usr/local/bin/psql which is HomeBrew's correct one. If you run brew doctor you should get a message stating that you need to add usr/local/bin to the head ...
How do you create a hidden div that doesn't create a line break or horizontal space?
... div from display: none to display: inline-block or equivalent without the now-displayed div taking up space and moving my other DOM elements around?
– bpromas
Sep 25 '15 at 18:23
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Renaming the current file in Vim
...es in the dir name?" -- A: the guy who started the project long ago who is now your boss... promoted out of coding into his true area of expertise: following development methodology fads and forcing them on the team.
– Stabledog
Apr 20 '13 at 13:03
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Efficient way to rotate a list in python
What is the most efficient way to rotate a list in python?
Right now I have something like this:
26 Answers
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How can I set up an editor to work with Git on Windows?
...eptember 2015 (6 years later)
The last release of git-for-Windows (2.5.3) now includes:
By configuring git config core.editor notepad, users can now use notepad.exe as their default editor.
Configuring git config format.commitMessageColumns 72 will be picked up by the notepad wrapper and line...
Error 1046 No database Selected, how to resolve?
... in SQL file. Can you please clarify that once more. I am having the issue now.
– Rahul S
Jul 15 '15 at 5:02
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Why do enum permissions often have 0, 1, 2, 4 values?
... == 00000010
Permissions.Delete == 4 == 00000100
Notice a pattern here? Now if we take my original example, i.e.,
var permissions = Permissions.Read | Permissions.Write;
Then...
permissions == 00000011
See? Both the Read and Write bits are set, and I can check that independently (Also not...