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How do I capture SIGINT in Python?
I'm working on a python script that starts several processes and database connections. Every now and then I want to kill the script with a Ctrl + C signal, and I'd like to do some cleanup.
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What does the star operator mean, in a function call?
...ence/collection into positional arguments, so you can do this:
def sum(a, b):
return a + b
values = (1, 2)
s = sum(*values)
This will unpack the tuple so that it actually executes as:
s = sum(1, 2)
The double star ** does the same, only using a dictionary and thus named arguments:
value...
Counting null and non-null values in a single query
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This works for Oracle and SQL Server (you might be able to get it to work on another RDBMS):
select sum(case when a is null then 1 else 0 end) count_nulls
, count(a) count_not_nulls
from us;
Or:
select count(*) - count(a), count(a) from us;
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How to change bower's default components folder?
I'm making a new project that uses bower from twitter. I created a component.json to maintain all my dependency like jquery. Then I run bower install that installs everything in a folder named components . But I need to install the components in a different folder, e.g. public/components .
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What's the difference between INNER JOIN, LEFT JOIN, RIGHT JOIN and FULL JOIN? [duplicate]
What's the difference between INNER JOIN , LEFT JOIN , RIGHT JOIN and FULL JOIN
in MySQL ?
3 Answers
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MySQL with Node.js
I've just started getting into Node.js. I come from a PHP background, so I'm fairly used to using MySQL for all my database needs.
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Splitting on last delimiter in Python string?
...u specify how many times to split, while str.rpartition() only splits once but always returns a fixed number of elements (prefix, delimiter & postfix) and is faster for the single split case.
Demo:
>>> s = "a,b,c,d"
>>> s.rsplit(',', 1)
['a,b,c', 'd']
>>> s.rsplit(',...
How to print third column to last column?
I'm trying to remove the first two columns (of which I'm not interested in) from a DbgView log file. I can't seem to find an example that prints from column 3 onwards until the end of the line. Note that each line has variable number of columns.
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How to activate an Anaconda environment
I'm on Windows 8, using Anaconda 1.7.5 64bit.
12 Answers
12
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Map function in MATLAB?
I'm a little surprised that MATLAB doesn't have a Map function, so I hacked one together myself since it's something I can't live without. Is there a better version out there? Is there a somewhat-standard functional programming library for MATLAB out there that I'm missing?
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