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Python Dictionary Comprehension
Is it possible to create a dictionary comprehension in Python (for the keys)?
8 Answers
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Why do we use arrays instead of other data structures?
As I was programming, I haven't seen an instance where an array is better for storing information than another form thereof. I had indeed figured the added "features" in programming languages had improved upon this and by that replaced them. I see now that they aren't replaced but rather given new ...
ADB not recognising Nexus 4 under Windows 7
I'm running on Windows 7, and I've updated all the drivers as it says on the Android developer website regarding using hardware devices. However, Eclipse is still not recognising my Nexus 4 when I try to run the application. The Android device chooser pops up, but it doesn't show anything on the h...
Difference between android-support-v7-appcompat and android-support-v4
... android-support-v7-appcompat.jar . If I want to add appcompat Action Bar in my application do I need to add both android-support-v7-appcompat.jar and android-support-v4.jar or only android-support-v7-appcompat.jar .
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Pandas groupby: How to get a union of strings
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In [4]: df = read_csv(StringIO(data),sep='\s+')
In [5]: df
Out[5]:
A B C
0 1 0.749065 This
1 2 0.301084 is
2 3 0.463468 a
3 4 0.643961 random
4 1 0.866521 string
5 2 0.120737 ...
What exactly does += do in python?
I need to know what += does in python. It's that simple. I also would appreciate links to definitions of other short hand tools in python.
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Suppress Scientific Notation in Numpy When Creating Array From Nested List
I have a nested Python list that looks like the following:
4 Answers
4
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Not equal != operator on NULL
Could someone please explain the following behavior in SQL?
11 Answers
11
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How to format a floating number to fixed width in Python
How do I format a floating number to a fixed width with the following requirements:
7 Answers
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From ND to 1D arrays
....ndarray.flatten (for a 1D copy) or np.ndarray.flat (for an 1D iterator):
In [12]: a = np.array([[1,2,3], [4,5,6]])
In [13]: b = a.ravel()
In [14]: b
Out[14]: array([1, 2, 3, 4, 5, 6])
Note that ravel() returns a view of a when possible. So modifying b also modifies a. ravel() returns a view wh...