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Extract date (yyyy/mm/dd) from a timestamp in PostgreSQL
...10
kworr
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answered May 26 '11 at 2:40
Wayne ConradWayne ...
What does axis in pandas mean?
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399
It specifies the axis along which the means are computed. By default axis=0. This is consisten...
Short description of the scoping rules?
...ctually, a concise rule for Python Scope resolution, from Learning Python, 3rd. Ed.. (These rules are specific to variable names, not attributes. If you reference it without a period, these rules apply.)
LEGB Rule
Local — Names assigned in any way within a function (def or lambda), and not decl...
List comprehension in Ruby
...k.nil?
self.collect(&block).compact
end
end
some_array = [1, 2, 3, 4, 5, 6]
new_array = some_array.comprehend {|x| x * 3 if x % 2 == 0}
puts new_array
Prints:
6
12
18
I would probably just do it the way you did though.
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Replace all elements of Python NumPy Array that are greater than some value
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346
I think both the fastest and most concise way to do this is to use NumPy's built-in Fancy inde...
Convert a list to a data frame
I have a nested list of data. Its length is 132 and each item is a list of length 20. Is there a quick way to convert this structure into a data frame that has 132 rows and 20 columns of data?
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Sublime Text 2 and 3: open the same file multiple times
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30
Go into the pane you want to see the file in.
Type Ctrl-p (Mac: ⌘-p) to get the list of file...
Int division: Why is the result of 1/3 == 0?
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The two operands (1 and 3) are integers, therefore integer arithmetic (division here) is used. Declaring the result variable as double just causes an implicit conversion to occur after division.
Integer division of course returns the true result of...
How to check if one of the following items is in a list?
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283
>>> L1 = [2,3,4]
>>> L2 = [1,2]
>>> [i for i in L1 if i in L2]
[2]
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Remove unwanted parts from strings in a column
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173
data['result'] = data['result'].map(lambda x: x.lstrip('+-').rstrip('aAbBcC'))
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