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Checking if sys.argv[x] is defined
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edited Nov 3 '17 at 13:12
answered Mar 24 '11 at 18:17
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CSS I want a div to be on top of everything
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122
In order for z-index to work, you'll need to give the element a position:absolute or a positio...
What is the difference between Python's list methods append and extend?
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append: Appends object at the end.
x = [1, 2, 3]
x.append([4, 5])
print (x)
gives you: [1, 2, 3, [4, 5]]
extend: Extends list by appending elements from the iterable.
x = [1, 2, 3]
x.extend([4, 5])
print (x)
gives you: [1, 2, 3, 4, 5]
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How to test multiple variables against a value?
...bout the same comparison for all names here. You are looking for:
if x == 1 or y == 1 or z == 1:
x and y are otherwise evaluated on their own (False if 0, True otherwise).
You can shorten that using a containment test against a tuple:
if 1 in (x, y, z):
or better still:
if 1 in {x, y, z}:
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How is set() implemented?
I've seen people say that set objects in python have O(1) membership-checking. How are they implemented internally to allow this? What sort of data structure does it use? What other implications does that implementation have?
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How to print third column to last column?
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19 Answers
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pull out p-values and r-squared from a linear regression
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12 Answers
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Git Extensions: Win32 error 487: Couldn't reserve space for cygwin's heap, Win32 error 0
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14 Answers
14
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How to request a random row in SQL?
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751
See this post: SQL to Select a random row from a database table. It goes through methods for doi...
If vs. Switch Speed
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185
The compiler can build jump tables where applicable. For example, when you use the reflector t...