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Understanding Python's “is” operator
...e value.
From the documentation for the is operator:
The operators is and is not test for object identity: x is y is true if and only if x and y are the same object.
Use the == operator instead:
print(x == y)
This prints True. x and y are two separate lists:
x[0] = 4
print(y) # prints [1...
How to define a function in ghci across multiple lines?
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For guards (like your example), you can just put them all on one line and it works (guards do not care about spacing)
let abs n | n >= 0 = n | otherwise = -n
If you wanted to write your function with multiple definitions that pattern match on the arguments, like this:
fact 0 = 1
fact n =...
Converting bytes to megabytes
... it is not correct actually because mega means 1 000 000. There is a new standard name for 220 bytes, it is mebibyte (http://en.wikipedia.org/wiki/Mebibyte) and it gathers popularity.
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improv...
jQuery slide left and show
I extended the jQuery effects called slideRightShow() and slideLeftHide() with a couple functions that work similarly to slideUp() and slideDown() as seen below. However, I would also like to implement slideLeftShow() and slideRightHide() .
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Simplest way to read json from a URL in java
This might be a dumb question but what is the simplest way to read and parse JSON from URL in Java ?
11 Answers
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Insert into a MySQL table or update if exists
...m what I've found, this method is less problematic for auto-increment keys and other unique key collisions than REPLACE INTO, and it is more efficient.
– Andrew Ensley
May 11 '12 at 21:27
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How do I convert a pandas Series or index to a Numpy array? [duplicate]
...d for a conversion.
Note: This attribute is also available for many other pandas' objects.
In [3]: df['A'].values
Out[3]: Out[16]: array([1, 2, 3])
To get the index as a list, call tolist:
In [4]: df.index.tolist()
Out[4]: ['a', 'b', 'c']
And similarly, for columns.
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How to move a model between two Django apps (Django 1.7)
So about a year ago I started a project and like all new developers I didn't really focus too much on the structure, however now I am further along with Django it has started to appear that my project layout mainly my models are horrible in structure.
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Converting a list to a set changes element order
...at when I am converting a list to set the order of elements is changed and is sorted by character.
11 Answers
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What is the difference between `let` and `var` in swift?
What is the difference between let and var in Apple's Swift language?
30 Answers
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