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Pandas groupby: How to get a union of strings
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In [5]: df
Out[5]:
A B C
0 1 0.749065 This
1 2 0.301084 is
2 3 0.463468 a
3 4 0.643961 random
4 1 0.866521 string
5 2 0.120737 !
In [6]: df.dtypes
Out[6]:
A int64
B float64
C object
dtype: object
When you apply your own function, t...
Numbering rows within groups in a data frame
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answered Oct 16 '12 at 23:41
mnelmnel
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What's the difference between lists enclosed by square brackets and parentheses in Python?
...you can change its contents:
>>> x = [1,2]
>>> x.append(3)
>>> x
[1, 2, 3]
while tuples are not:
>>> x = (1,2)
>>> x
(1, 2)
>>> x.append(3)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AttributeError: '...
ADT requires 'org.eclipse.wst.sse.core 0.0.0' but it could not be found
...
I've just encountered exactly the same problem in Eclipse 3.6 (Helios). After plenty of Googling I came across this link:
http://code.google.com/intl/es/eclipse/docs/faq.html#wstinstallerror
During installation, there's an error
about requiring
org.eclipse.wst.sse.ui. How d...
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...
What does the 'b' character do in front of a string literal?
... it indicates that the
literal should become a bytes literal
in Python 3 (e.g. when code is
automatically converted with 2to3). A
'u' or 'b' prefix may be followed by
an 'r' prefix.
The Python 3 documentation states:
Bytes literals are always prefixed with 'b' or 'B'; they produce an...
Numpy: Get random set of rows from 2D array
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>>> A = np.random.randint(5, size=(10,3))
>>> A
array([[1, 3, 0],
[3, 2, 0],
[0, 2, 1],
[1, 1, 4],
[3, 2, 2],
[0, 1, 0],
[1, 3, 1],
[0, 4, 1],
[2, 4, 2],
[3, 3, 1]])
>>> idx = np.ran...
Python String and Integer concatenation [duplicate]
...kticks) is deprecated in later versions of Python 2, and removed in Python 3. Use the str() function instead.
You can use :
string = 'string'
for i in range(11):
string +=`i`
print string
It will print string012345678910.
To get string0, string1 ..... string10 you can use this as @YOU suggeste...