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How do I implement an Objective-C singleton that is compatible with ARC?
How do I convert (or create) a singleton class that compiles and behaves correctly when using automatic reference counting (ARC) in Xcode 4.2?
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Python != operation vs “is not”
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== is an equality test. It checks whether the right hand side and the left hand side are equal objects (according to their __eq__ or __cmp__ methods.)
is is an identity test. It checks whether the right hand side and the left hand side are the very same object. No methodcalls ...
Converting dd/mm/yyyy formatted string to Datetime [duplicate]
I am new to DotNet and C#. I want to convert a string in mm/dd/yyyy format to DateTime object. I tried the parse function like below but it is throwing a runtime error.
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Drawing Isometric game worlds
...echnique for mapping the tiles to the screen can be said that the tile's x and y coordinates are on the vertical and horizontal axes.
"Drawing in a diamond" approach:
By drawing an isometric map using "drawing in a diamond", which I believe refers to just rendering the map by using a nested for-lo...
What is the recommended batch size for SqlBulkCopy?
...s my SQL Server instance. Using a custom IDataReader, it parses flat files and inserts them into a database using SQLBulkCopy. A typical file has about 6M qualified rows, averaging 5 columns of decimal and short text, about 30 bytes per row.
Given this scenario, I found a batch size of 5,000 to be...
How many levels of pointers can we have?
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The C standard specifies the lower limit:
5.2.4.1 Translation limits
276 The implementation shall be able to translate and execute at least one program that contains at least one instance of every one of the following limits...
MVC4 StyleBundle not resolving images
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According to this thread on MVC4 css bundling and image references, if you define your bundle as:
bundles.Add(new StyleBundle("~/Content/css/jquery-ui/bundle")
.Include("~/Content/css/jquery-ui/*.css"));
Where you define the bundle on the same path ...
How to prune local tracking branches that do not exist on remote anymore
...es.
This line should do the trick (requires bash or zsh, won't work with standard Bourne shell):
git branch -r | awk '{print $1}' | egrep -v -f /dev/fd/0 <(git branch -vv | grep origin) | awk '{print $1}' | xargs git branch -d
This string gets the list of remote branches and passes it into egrep...
Sort array of objects by string property value
...are function body: return a.value - b.value; (ASC)
– Andre Figueiredo
Jan 8 '14 at 12:06
23
@Cerb...
How to add an extra column to a NumPy array
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I think a more straightforward solution and faster to boot is to do the following:
import numpy as np
N = 10
a = np.random.rand(N,N)
b = np.zeros((N,N+1))
b[:,:-1] = a
And timings:
In [23]: N = 10
In [24]: a = np.random.rand(N,N)
In [25]: %timeit b = np.hstac...