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Quickly reading very large tables as dataframes
I have very large tables (30 million rows) that I would like to load as a dataframes in R. read.table() has a lot of convenient features, but it seems like there is a lot of logic in the implementation that would slow things down. In my case, I am assuming I know the types of the columns ahead o...
How to convert list of tuples to multiple lists?
Suppose I have a list of tuples and I want to convert to multiple lists.
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Generating all permutations of a given string
What is an elegant way to find all the permutations of a string. E.g. permutation for ba , would be ba and ab , but what about longer string such as abcdefgh ? Is there any Java implementation example?
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How can I find the first occurrence of a sub-string in a python string?
So if my string is "the dude is a cool dude".
I'd like to find the first index of 'dude':
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Why use double indirection? or Why use pointers to pointers?
When should a double indirection be used in C? Can anyone explain with a example?
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Why can't I have “public static const string S = ”stuff"; in my Class?
When trying to compile my class I get an error:
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Why are Where and Select outperforming just Select?
I have a class, like this:
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How to get overall CPU usage (e.g. 57%) on Linux [closed]
I am wondering how you can get the system CPU usage and present it in percent using bash, for example.
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Set folder browser dialog start location
Is there any way to set the initial directory of a folder browser dialog to a non-special folder? This is what I'm currently using
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What does a tilde do when it precedes an expression?
I saw it in an answer, and I've never seen it before.
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