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Convert column classes in data.table
...rter)]
str(dtnew)
Classes ‘data.table’ and 'data.frame': 10 obs. of 3 variables:
$ ID : Factor w/ 2 levels "A","B": 1 1 1 1 1 2 2 2 2 2
$ Quarter: chr "1" "2" "3" "4" ...
$ value : num -0.838 0.146 -1.059 -1.197 0.282 ...
Using lapply and as.character:
dtnew <- dt[, lapply(....
Preserving signatures of decorated functions
...))
return f(*args, **kwargs)
@args_as_ints
def funny_function(x, y, z=3):
"""Computes x*y + 2*z"""
return x*y + 2*z
print funny_function("3", 4.0, z="5")
# 22
help(funny_function)
# Help on function funny_function in module __main__:
#
# funny_function(x, y, z=3)
# Computes x*y + ...
How to return dictionary keys as a list in Python?
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answered May 29 '13 at 16:25
Chris Chris
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How to install pip with Python 3?
I want to install pip . It should support Python 3, but it requires setuptools, which is available only for Python 2.
21 A...
How to calculate the number of occurrence of a given character in each row of a column of strings?
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13 Answers
13
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The modulo operation on negative numbers in Python
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134
Unlike C or C++, Python's modulo operator (%) always return a number having the same sign as th...
How does the bitwise complement operator (~ tilde) work?
Why is it that ~2 is equal to -3? How does ~ operator work?
15 Answers
15
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Numbering rows within groups in a data frame
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answered Oct 16 '12 at 23:41
mnelmnel
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Java: how can I split an ArrayList in multiple small ArrayLists?
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332
You can use subList(int fromIndex, int toIndex) to get a view of a portion of the original lis...