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Add column with constant value to pandas dataframe [duplicate]
...with partially aligned indices:
In [7]: from pandas import DataFrame
In [8]: from numpy.random import randint
In [9]: df = DataFrame({'a': randint(3, size=10)})
In [10]:
In [10]: df
Out[10]:
a
0 0
1 2
2 0
3 1
4 0
5 0
6 0
7 0
8 0
9 0
In [11]: s = df.a[:5]
In [12]: dfa, sa = df.ali...
undefined method `source_index' for Gem:Module (NoMethodError)
... this problem myself while trying to upgrade an older Rails app from REE 1.8.7 to 1.9.3-p385. Oddly, Ruby 1.9.3-p327 works just fine. What it came down to was ruby-1.9.3-p385 had installed RubyGems version 2.0.2 for me, and 1.9.3-p327 has RubyGems v1.8.23 installed.
Gem.source_index has been deprec...
How to get the last N rows of a pandas DataFrame?
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408
Don't forget DataFrame.tail! e.g. df1.tail(10)
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In Maven 2, how do I know from which dependency comes a transitive dependency?
...NAPSHOT
[INFO] \- org.apache.maven.doxia:doxia-site-renderer:jar:1.0-alpha-8:compile
[INFO] \- org.codehaus.plexus:plexus-velocity:jar:1.1.3:compile
[INFO] \- velocity:velocity:jar:1.4:compile
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How to drop into REPL (Read, Eval, Print, Loop) from Python code
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answered Sep 8 '09 at 20:34
AlexAlex
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Check if a given Type is an Enum
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answered Nov 8 '11 at 2:35
Ry-♦Ry-
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How to get the index of a maximum element in a numpy array along one axis
...iroeumiro
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Change a column type from Date to DateTime during ROR migration
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answered Mar 4 '11 at 8:42
apneadivingapneadiving
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Is std::vector so much slower than plain arrays?
...ds
UseVector completed in 4.412 seconds
UseVectorPushBack completed in 8.017 seconds
The whole thing completed in 14.626 seconds
So array is twice as quick as vector.
But after looking at the code in more detail this is expected; as you run across the vector twice and the array only once...