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What is a word boundary in regex?
...ic output, among other purposes) and cannot find a precise definition of \b ("word boundary"). I had assumed that -12 would be an "integer word" (matched by \b\-?\d+\b ) but it appears that this does not work. I'd be grateful to know of ways of matching space-separated numbers.
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Get statistics for each group (such as count, mean, etc) using pandas GroupBy?
I have a data frame df and I use several columns from it to groupby :
7 Answers
7
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How to define an enumerated type (enum) in C?
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Declaring an enum variable is done like this:
enum strategy {RANDOM, IMMEDIATE, SEARCH};
enum strategy my_strategy = IMMEDIATE;
However, you can use a typedef to shorten the variable declarations, like so:
typedef enum {RANDOM, IMMEDIATE, SEARC...
Append a NumPy array to a NumPy array
I have a numpy_array. Something like [ a b c ] .
9 Answers
9
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Converting bool to text in C++
Maybe this is a dumb question, but is there any way to convert a boolean value to a string such that 1 turns to "true" and 0 turns to "false"? I could just use an if statement, but it would be nice to know if there is a way to do that with the language or standard libraries. Plus, I'm a pedant. :...
How does this code generate the map of India?
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The long string is simply a binary sequence converted to ASCII. The first for statement makes b start out at 10, and the [b+++21] after the string yields 31. Treating the string as an array, offset 31 is the start of the "real" data in the string (the...
Java Generics (Wildcards)
I have a couple of questions about generic wildcards in Java:
6 Answers
6
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Convert list of dictionaries to a pandas DataFrame
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cs95
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answered Dec 17 '13 at 15:35
jorisjoris
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Pandas: drop a level from a multi-level column index?
...ltiIndex.droplevel:
>>> cols = pd.MultiIndex.from_tuples([("a", "b"), ("a", "c")])
>>> df = pd.DataFrame([[1,2], [3,4]], columns=cols)
>>> df
a
b c
0 1 2
1 3 4
[2 rows x 2 columns]
>>> df.columns = df.columns.droplevel()
>>> df
b c
0 ...
Naming returned columns in Pandas aggregate function? [duplicate]
I'm having trouble with Pandas' groupby functionality. I've read the documentation , but I can't see to figure out how to apply aggregate functions to multiple columns and have custom names for those columns.
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