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Understanding exactly when a data.table is a reference to (vs a copy of) another data.table
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143
Yes, it's subassignment in R using <- (or = or ->) that makes a copy of the whole object...
Format number to 2 decimal places
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edited Oct 22 '18 at 9:57
Madhur Bhaiya
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How to find the length of a string in R
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See ?nchar. For example:
> nchar("foo")
[1] 3
> set.seed(10)
> strn <- paste(sample(LETTERS, 10), collapse = "")
> strn
[1] "NHKPBEFTLY"
> nchar(strn)
[1] 10
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Exit a Script On Error
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138
Are you looking for exit?
This is the best bash guide around.
http://tldp.org/LDP/abs/html/
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Import pandas dataframe column as string not int
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154
Just want to reiterate this will work in pandas >= 0.9.1:
In [2]: read_csv('sample.csv', d...
Usage of sys.stdout.flush() method
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179
Python's standard out is buffered (meaning that it collects some of the data "written" to stan...
python pandas: apply a function with arguments to a series
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170
Newer versions of pandas do allow you to pass extra arguments (see the new documentation). So ...
Error in : object of type 'closure' is not subsettable
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120
In general this error message means that you have tried to use indexing on a function. You ca...
Does Ruby regular expression have a not match operator like “!~” in Perl?
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156
Yes: !~ works just fine – you probably thought it wouldn’t because it’s missing from the...
How to replace all strings to numbers contained in each string in Notepad++?
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191
In Notepad++ to replace, hit Ctrl+H to open the Replace menu.
Then if you check the "Regular ...