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Pandas DataFrame Groupby two columns and get counts
I have a pandas dataframe in the following format:
6 Answers
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Bash tool to get nth line from a file
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head and pipe with tail will be slow for a huge file. I would suggest sed like this:
sed 'NUMq;d' file
Where NUM is the number of the line you want to print; so, for example, sed '10q;d' file to print the 10th line of file.
Ex...
ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock'
I installed LAMP on Ubuntu 12.04 LTS (Precise Pangolin) and then set root password on phpMyAdmin . I forgot the password and now I am unable to login. When I try to change password through terminal I get:
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Using Core Data, iCloud and CloudKit for syncing and backup and how it works together
...am in the early stages of creating an app where I would like to save, sync and backup data. The app will not store any files just data in a database. It is going to be iOS 8 and up so I am able to use CloudKit. I did some research and still not clear on how Core Data, iCloud and CloudKit work toge...
HTML: Include, or exclude, optional closing tags?
...unless I have a very good reason not to) because it lends to more readable and updateable code.
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What is the email subject length limit?
...e RFC 2822, section 2.1.1 to start.
There are two limits that this
standard places on the number of
characters in a line. Each line of
characters MUST be no more than 998
characters, and SHOULD be no more than
78 characters, excluding the CRLF.
As the RFC states later, you can work a...
Replacing a 32-bit loop counter with 64-bit introduces crazy performance deviations with _mm_popcnt_
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Culprit: False Data Dependency (and the compiler isn't even aware of it)
On Sandy/Ivy Bridge and Haswell processors, the instruction:
popcnt src, dest
appears to have a false dependency on the destination register dest. Even though the instruction only...
Using try vs if in python
...er LBYL style ("look before you leap"). To me, it's a matter of efficiency and readability.
In your example (say that instead of returning a list or an empty string, the function were to return a list or None), if you expect that 99 % of the time result will actually contain something iterable, I'd...
How are msys, msys2, and msysgit related to each other?
.... (It's entirely possible I just don't know what to look for.) I do understand that MSYS is a minimal port of Linux tools to support development using MinGW, but I'm not clear on the relationship between the three of them or the teams that developed/maintain them.
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How can I combine flexbox and vertical scroll in a full-height app?
...xbox. I found what I want using old flexbox layout module ( display: box; and other things) in this link: CSS3 Flexbox full-height app and overflow
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