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Drop unused factor levels in a subsetted data frame
...r . When I create a subset of this dataframe using subset or another indexing function, a new data frame is created. However, the factor variable retains all of its original levels, even when/if they do not exist in the new dataframe.
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input() error - NameError: name '…' is not defined
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input function in Python 2.7, evaluates whatever your enter, as a Python expression. If you simply want to read strings, then use raw_input function in Python 2.7, which will not evaluate the read strings.
If you are using Python 3.x, raw_input has been renamed to input. Quoting the Python 3.0 rel...
Getting current unixtimestamp using Moment.js
I want to get the Unix TimeStamp using Moment.js.
I can find many functions which convert timestamp to date in moment.js.
I know that I can easily get the unix timestamp by using the following JavaScript function: Math.floor(new Date().getTime()/1000) .
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Distinct by property of class with LINQ [duplicate]
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I think that no Overhead exists!
– Amirhossein Mehrvarzi
Dec 23 '13 at 13:47
6
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How to overload __init__ method based on argument type?
...')]
The reason it's neater is that there is no doubt about what type is expected, and you aren't forced to guess at what the caller intended for you to do with the datatype it gave you. The problem with isinstance(x, basestring) is that there is no way for the caller to tell you, for instance, tha...
Remove xticks in a matplotlib plot?
I have a semilogx plot and I would like to remove the xticks. I tried:
9 Answers
9
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How to make the hardware beep sound in Mac OS X 10.6
I just want that Mac OS X 10.6 does a hardware beep sound like in open suse and other distributions. I tried following approaches
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Trimming a huge (3.5 GB) csv file to read into R
...ears.
file_in <- file("in.csv","r")
file_out <- file("out.csv","a")
x <- readLines(file_in, n=1)
writeLines(x, file_out) # copy headers
B <- 300000 # depends how large is one pack
while(length(x)) {
ind <- grep("^[^;]*;[^;]*; 20(09|10)", x)
if (length(ind)) writeLines(x[ind]...
Library not loaded: libmysqlclient.16.dylib error when trying to run 'rails server' on OS X 10.6 wit
...hat link will resolve to the location where it's actually installed. On OS X, that's usually under /usr/local/mysql/lib, which is where this command links to. If your lib is installed in a different location, you'll need to tweak this command. Type locate libmysqlclient.18.dylib and substitute the ...
Correct way to define C++ namespace methods in .cpp file
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Calling #2 "wrong" is a huge exaggeration. By this logic, all symbol names are "wrong" because they can potentially hide other symbol names in other scopes.
– tenfour
Dec 30 '11 at 16:59
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