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unix domain socket VS named pipes?
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108
UNIX-domain sockets are generally more flexible than named pipes. Some of their advantages ar...
How to set limits for axes in ggplot2 R plots?
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edited Jun 8 '17 at 11:37
Axeman
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ans...
How can I convert a file pointer ( FILE* fp ) to a file descriptor (int fd)?
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214
The proper function is int fileno(FILE *stream). It can be found in <stdio.h>, and is a P...
How do I tell matplotlib that I am done with a plot?
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You can use figure to create a new plot, for example, or use close after the first plot.
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How do I get SUM function in MySQL to return '0' if no values are found?
...ee it in action, please see this sql fiddle: http://www.sqlfiddle.com/#!2/d1542/3/0
More Information:
Given three tables (one with all numbers, one with all nulls, and one with a mixture):
SQL Fiddle
MySQL 5.5.32 Schema Setup:
CREATE TABLE foo
(
id INT NOT NULL AUTO_INCREMENT PRIMARY KEY...
How to access pandas groupby dataframe by key
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198
You can use the get_group method:
In [21]: gb.get_group('foo')
Out[21]:
A B C...
How to hide command output in Bash
...dy listening?" >&-
Usually, output goes either to file descriptor 1 (stdout) or 2 (stderr). If you close a file descriptor, you'll have to do so for every numbered descriptor, as &> (below) is a special BASH syntax incompatible with >&-:
/your/first/command >&- 2>&a...
Is it possible for a unit test to assert that a method calls sys.exit()
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Yes. sys.exit raises SystemExit, so you can check it with assertRaises:
with self.assertRaise...
C#/Linq: Apply a mapping function to each element in an IEnumerable?
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181
You can just use the Select() extension method:
IEnumerable<int> integers = new List<...
How can I increment a char?
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180
In Python 2.x, just use the ord and chr functions:
>>> ord('c')
99
>>> ord(...