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Combine two data frames by rows (rbind) when they have different sets of columns
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@MERose Hadley: "Yes, all dplyr methods ignore rownames."
– zx8754
Dec 7 '17 at 9:11
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How to activate virtualenv?
... virtualenv venv --distribute
New python executable in venv/bin/python
Installing distribute.........done.
Installing pip................done.
$ source venv/bin/activate
(venv)$ python
share
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impr...
Profiling Django
...at queries are executed on each page and how much time they take. It's a really useful, powerful and easy to use tool.
Also, read recommendations about Django performance in Database access optimization from the documentation.
And Django performance tips by
Jacob Kaplan-Moss.
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Should Javadoc comments be added to the implementation?
...methods that are implementation only (not overrides), sure, why not, especially if they are public.
If you have an overriding situation and you are going to replicate any text, then definitely not. Replication is a surefire way of causing discrepancies. As a result, users would have a different und...
Xcode Command /usr/bin/codesign failed with exit code 1 : errSecInternalComponent
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Open Keychain Access, then in the File menu select Lock All Keychains.
Then go back to Xcode and clean and rebuild. It will prompt you for your password again to unlock the keychain.
After this, assuming you have no other compile issues, it will succeed!
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Twitter Bootstrap - how to center elements horizontally or vertically
is there any way to center html elements vertically or horizontally inside the main parents?
12 Answers
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I want to remove double quotes from a String
...(/['"]+/g, ''));
That should do the trick... (if your goal is to replace all double quotes).
Here's how it works:
['"] is a character class, matches both single and double quotes. you can replace this with " to only match double quotes.
+: one or more quotes, chars, as defined by the preceding ...
How to keep one variable constant with other one changing with row in excel
...ing the formula into new cells.
Since you are dragging across rows, you really only need to freeze the row part:
=(B0+4)/A$0
Keyboard Shortcuts
Commenters helpfully pointed out that you can toggle relative addressing for a formula in the currently selected cells with these keyboard shortcuts:...
How to get first and last day of the week in JavaScript
...tring(); just I have corrected the @RichardN's code, which is having a small mistake
– Azeez
Oct 13 '14 at 14:20
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Unable to create/open lock file: /data/mongod.lock errno:13 Permission denied
How to I get mongo to use a mounted drive on ec2? I really do not understand. I attached a volume on ec2 formatted the drive as root and start as root and yet as root I cant access? I am running on ubuntu 12.04. No other mongo is running
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