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Python pandas Filtering out nan from a data selection of a column of strings
...N:
In [87]:
nms
Out[87]:
movie name rating
0 thg John 3
1 thg NaN 4
3 mol Graham NaN
4 lob NaN NaN
5 lob NaN NaN
[5 rows x 3 columns]
In [89]:
nms = nms.dropna(thresh=2)
In [90]:
nms[nms.name.notnull()]
Out[90]:
movie name rating
0 ...
What does the regular expression /_/g mean?
...
152
The regex matches the _ character.
The g means Global, and causes the replace call to replace...
Generate full SQL script from EF 5 Code First Migrations
...
answered Dec 18 '12 at 18:44
Matt WilsonMatt Wilson
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invalid target release: 1.7
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159
You need to set JAVA_HOME to your jdk7 home directory, for example on Microsoft Windows:
"C:...
How do you append to an already existing string?
...
215
In classic sh, you have to do something like:
s=test1
s="${s}test2"
(there are lots of varia...
What is the significance of ProjectTypeGuids tag in the visual studio project file
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139
{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC} is the GUID for C# project
{60dc8134-eba5-43b8-bcc9-bb...
Transpose a data frame
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109
You'd better not transpose the data.frame while the name column is in it - all numeric values ...
Where in an Eclipse workspace is the list of projects stored?
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153
Windows:
<workspace>\.metadata\.plugins\org.eclipse.core.resources\.projects\
Linux /...
Get current batchfile directory
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511
System read-only variable %CD% keeps the path of the caller of the batch, not the batch file lo...
Python creating a dictionary of lists
...s import defaultdict
>>> d = defaultdict(list)
>>> a = ['1', '2']
>>> for i in a:
... for j in range(int(i), int(i) + 2):
... d[j].append(i)
...
>>> d
defaultdict(<type 'list'>, {1: ['1'], 2: ['1', '2'], 3: ['2']})
>>> d.items()
[(1, ['1']), (...