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What is the most efficient way to create a dictionary of two pandas Dataframe columns?
...ies(df.Letter.values,index=df.Position).to_dict()
Out[9]: {1: 'a', 2: 'b', 3: 'c', 4: 'd', 5: 'e'}
Speed comparion (using Wouter's method)
In [6]: df = pd.DataFrame(randint(0,10,10000).reshape(5000,2),columns=list('AB'))
In [7]: %timeit dict(zip(df.A,df.B))
1000 loops, best of 3: 1.27 ms per loo...
How to convert list of tuples to multiple lists?
... function zip() will almost do what you want:
>>> zip(*[(1, 2), (3, 4), (5, 6)])
[(1, 3, 5), (2, 4, 6)]
The only difference is that you get tuples instead of lists. You can convert them to lists using
map(list, zip(*[(1, 2), (3, 4), (5, 6)]))
...
Backporting Python 3 open(encoding=“utf-8”) to Python 2
I have a Python codebase, built for Python 3, which uses Python 3 style open() with encoding parameter:
6 Answers
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Ruby Hash to array of values
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Ray ToalRay Toal
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3
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Split column at delimiter in data frame [duplicate]
...me.
I added a "x|y" line to avoid ambiguities:
df <- data.frame(ID=11:13, FOO=c('a|b','b|c','x|y'))
foo <- data.frame(do.call('rbind', strsplit(as.character(df$FOO),'|',fixed=TRUE)))
Or, if you want to replace the columns in the existing data.frame:
within(df, FOO<-data.frame(do.call('r...
Struct inheritance in C++
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answered Jun 11 '09 at 3:44
Alex MartelliAlex Martelli
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If vs. Switch Speed
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answered Jan 14 '09 at 23:16
Konrad RudolphKonrad Rudolph
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Plot a legend outside of the plotting area in base graphics?
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113
Maybe what you need is par(xpd=TRUE) to enable things to be drawn outside the plot region. So if...
