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if/else in a list comprehension
...x in row]
In general,
[f(x) if condition else g(x) for x in sequence]
And, for list comprehensions with if conditions only,
[f(x) for x in sequence if condition]
Note that this actually uses a different language construct, a conditional expression, which itself is not part of the comprehensi...
Use git “log” command in another folder
...e folder B. Folder B is another git project (so log is different between A and B).
2 Answers
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Create numpy matrix filled with NaNs
...oops for vector operations in numpy.
You can create an uninitialized array and assign to all entries at once:
>>> a = numpy.empty((3,3,))
>>> a[:] = numpy.nan
>>> a
array([[ NaN, NaN, NaN],
[ NaN, NaN, NaN],
[ NaN, NaN, NaN]])
I have timed the alte...
How do I filter query objects by date range in Django?
...omparing against a DateTimeField, instead of messing about with throwaway (and confusing) datetime objects. See further explanation in comments below.
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How to use RestSharp with async/await
...dern example of some asynchronous C# code that uses RestSharp with async and await . I know there's been a recent update by Haack but I don't know how to use the new methods.
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Android Studio rendering problems
I'm using Android Studio 0.2.3 and when opened an activity layout normally, the preview should appear on the right side, so that I can switch between Text and Design mode, which should again show the preview of the layout.
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How can I create tests in Android Studio?
Just downloaded Android Studio which is based off of the Intellij Idea.
12 Answers
12
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Array include any value from another array?
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(cheeses & foods).empty?
As Marc-André Lafortune said in comments, & works in linear time while any? + include? will be quadratic. For larger sets of data, linear time will be faster. For small data sets, any? + include? may be faster as shown by Lee Ja...
ReSharper warns: “Static field in generic type”
...lass C<T> which
has a static field X, the values of C<int>.X and C<string>.X
have completely different, independent values.
In the rare cases when you do need the 'specialized' static fields,
feel free to suppress the warning.
If you need to have a static field shar...
In a javascript array, how do I get the last 5 elements, excluding the first element?
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+1 simple and useful. Additionally I think last value (1) must be 0 to work, This arr.slice(Math.max(arr.length - 5, 0)) worked for me.
– QMaster
Nov 1 '14 at 21:41
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