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undefined reference to boost::system::system_category() when compiling
...raries. I have the 1.46-dev Boost libraries from the Ubuntu Repository installed, but I get an error when compiling the program.
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matplotlib Legend Markers Only Once
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I like to change my matplotlib rc parameters dynamically in every python script. To achieve this goal I simply use somthing like that at the beginning of my python files.
from pylab import *
rcParams['legend.numpoints'] = 1
This will apply to all plots generated from my pyt...
How to add an auto-incrementing primary key to an existing table, in PostgreSQL?
...of PostgreSQL
In old versions of PostgreSQL (prior to 8.x?) you had to do all the dirty work. The following sequence of commands should do the trick:
ALTER TABLE test1 ADD COLUMN id INTEGER;
CREATE SEQUENCE test_id_seq OWNED BY test1.id;
ALTER TABLE test ALTER COLUMN id SET DEFAULT nextval('...
What is the different between 'Auto' and '*' when setting width/height for a grid column?
...elements within it require.
The width of * sized columns is calculated by allocating space for the Auto, and fixed width columns, and then dividing up the remaining space. So if there's only one * sized column, it will get all the remaining space, if there were two they would get half each, etc. Yo...
Redirect stdout to a file in Python?
...t it back when you're done, sys.stdout = stdout. That way if you're being called from a function that uses print you don't screw them up.
– mgold
Dec 20 '12 at 15:06
4
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What's the status of multicore programming in Haskell?
...012 period, the following things have happened:
2012:
From 2012, the parallel Haskell status updates began appearing in the Parallel Haskell Digest.
2011:
Parallel and Concurrent Programming in Haskell, a tutorial. version 1.1 released by Simon Marlow
Haskell and parallelism, mentioned in an ...
What is javax.inject.Named annotation supposed to be used for?
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So @Named really is @Qualifier, so why is @Qualifier required to be so generic, is the idea to allow someone using javax.inject to define stereotypes like @Repository,@Service,@Controller that are marked up as @Qualifier?
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MySql: Tinyint (2) vs tinyint(1) - what is the difference?
...several mysql clients (navicat, sequel pro).
It does not mean anything AT ALL! I ran a test, all above clients or even the command-line client seems to ignore this.
But, display width is most important if you are using ZEROFILL option, for example your table has following 2 columns:
A tinyint(2) ...
What is a mixin, and why are they useful?
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Probably not an issue in this example, but you generally want to put the main base class as the last element within the parenthesis so to create the inheritance chain: Request==>Mixin==>...==>BaseRequest. See here: ianlewis.org/en/mixins-and-python
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What is the difference between require_relative and require in Ruby?
... the docs:
require_relative complements the builtin method require by allowing you to load a file that is relative to the file containing the require_relative statement.
For example, if you have unit test classes in the "test" directory, and data for them under the test "test/data" directo...