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Filtering a list based on a list of booleans

...se] >>> list(compress(list_a, fil)) [1, 4] Timing comparisons(py3.x): >>> list_a = [1, 2, 4, 6] >>> fil = [True, False, True, False] >>> %timeit list(compress(list_a, fil)) 100000 loops, best of 3: 2.58 us per loop >>> %timeit [i for (i, v) in zip(list...
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What does the star operator mean, in a function call?

... 932 The single star * unpacks the sequence/collection into positional arguments, so you can do this...
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Specify custom Date format for colClasses argument in read.table/read.csv

...rom) as.Date(from, format="%d/%m/%Y") ) tmp <- c("1, 15/08/2008", "2, 23/05/2010") con <- textConnection(tmp) tmp2 <- read.csv(con, colClasses=c('numeric','myDate'), header=FALSE) str(tmp2) Then modify if needed to work for your data. Edit --- You might want to run setClass('myDate') ...
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sed: print only matching group

...eplaced with the contents of the group echo "foo bar <foo> bla 1 2 3.4" | sed -n 's/.*\([0-9][0-9]*[\ \t][0-9.]*[ \t]*$\)/\1/p' 2 3.4 share | improve this answer | ...
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Column order manipulation using col-lg-push and col-lg-pull in Twitter Bootstrap 3

I'm now reading documentation on Twitter Bootstrap 3, and tried to follow column ordering as shown in this page but hit the wall. I don't understand why such a code works nor how to correctly specify the setting. What I want to show is one grid, which is consisted of length 5, and the other leng...
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NPM - How to fix “No readme data”

...o, when you read that warning, ensure that the problem is not related to a 3rd party package. share | improve this answer | follow | ...
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What does the slash mean in help() output?

What does the / mean in Python 3.4's help output for range before the closing parenthesis? 3 Answers ...
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Mean per group in a data.frame [duplicate]

....table(text= 'Name Month Rate1 Rate2 Aira 1 12 23 Aira 2 18 73 Aira 3 19 45 Ben 1 53 19 Ben 2 22 87 Ben 3 19 45 Cat 1 22 87 Cat 2 67 43 Cat ...
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How to get the first column of a pandas DataFrame as a Series?

... 143 >>> import pandas as pd >>> df = pd.DataFrame({'x' : [1, 2, 3, 4], 'y' : [4, 5...
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What does “%” (percent) do in PowerShell?

... 3 Answers 3 Active ...