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How to drop columns by name in a data frame
I have a large data set and I would like to read specific columns or drop all the others.
11 Answers
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How do I clone a generic list in C#?
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I think List.ConvertAll might do this in faster time, since it can pre-allocate the entire array for the list, versus having to resize all the time.
– MichaelGG
Oct 21 '08 at 17:43
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Generate pdf from HTML in div using Javascript
...lement IDs are still done in jQuery style "#id", but it does not mean that all jQuery selectors are supported.
Therefore replacing '#ignorePDF' with class selectors like '.ignorePDF' did not work for me. Instead you will have to add the same handler for each and every element, which you want to ig...
Evaluate expression given as a string
...s("5+5")
[1] "character"
> class(parse(text="5+5"))
[1] "expression"
Calling eval() invokes many behaviours, some are not immediately obvious:
> class(eval(parse(text="5+5")))
[1] "numeric"
> class(eval(parse(text="gray")))
[1] "function"
> class(eval(parse(text="blue")))
Error in eva...
Read lines from a file into a Bash array [duplicate]
... from BinaryZebra's comment
and tested here. The addition of command eval allows for the expression to be kept in the present execution environment while the expressions before are only held for the duration of the eval.
Use $IFS that has no spaces\tabs, just newlines/CR
$ IFS=$'\r\n' GLOBIGNORE=...
Stylecop vs FXcop
...e. It makes decisions regarding style primarily to avoid holy wars (after all, style is almost always an inherently subjective thing). I don't think I've ever met someone who liked all of StyleCop's rules, but that's ok. It means that StyleCop is a generally good compromise amongst the vast set o...
setImmediate vs. nextTick
... changes documentation suggests using it when doing recursive nextTick calls.
7 Answers
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How to compare a local git branch with its remote branch?
...rbranch_path> <remotebranch_path>
You can git branch -a to list all branches (local and remote) then choose branch name from list (just remove remotes/ from remote branch name.
Example: git diff master origin/master (where "master" is local master branch and "origin/master" is a remote n...
how to remove shared preference while application uninstall in android
...nd password via SharedPreferences thats works fine, but i need to remove all my used SharedPreferences while my application uninstall. How to do it?
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How to open an elevated cmd using command line for Windows?
... batch file with this and saved it as admincmd.bat in my windows folder so all I have to do is type "admincmd" hit enter and it opens an admin cmd.(I also added another line to the batch file with "exit" so it closes the non admin cmd window)
– Tony Brix
Nov 16...