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Convert data.frame column format from character to factor
... would like to change the format (class) of some columns of my data.frame object ( mydf ) from charactor to factor .
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What does the regular expression /_/g mean?
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The regex matches the _ character.
The g means Global, and causes the replace call to replace all matches, not just the first one.
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How can you list the matches of Vim's search?
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" put in your ~/.vimrc file
" START search related configs and helps
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" ignore case when searching
set ignorecase
" search as characters are entered, as you type in more characters, the search is refined
set incsearch
" highlight matches, in normal mode ...
Regex for quoted string with escaping quotes
How do I get the substring " It's big \"problem " using a regular expression?
16 Answers
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How can I configure my makefile for debug and release builds?
I have the following makefile for my project, and I'd like to configure it for release and debug builds. In my code, I have lots of #ifdef DEBUG macros in place, so it's simply a matter of setting this macro and adding the -g3 -gdwarf2 flags to the compilers. How can I do this?
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Calling C++ class methods via a function pointer
How do I obtain a function pointer for a class member function, and later call that member function with a specific object? I’d like to write:
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Is C++ context-free or context-sensitive?
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Below is my (current) favorite demonstration of why parsing C++ is (probably) Turing-complete, since it shows a program which is syntactically correct if and only if a given integer is prime.
So I assert that C++ is neither ...
undefined reference to boost::system::system_category() when compiling
I'm trying to compile a program on Ubuntu 11.10 that uses the Boost libraries. I have the 1.46-dev Boost libraries from the Ubuntu Repository installed, but I get an error when compiling the program.
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form serialize javascript (no framework)
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The miniature from-serialize library doesn't rely on a framework. Other than something like that, you'll need to implement the serialization function yourself. (though at a weight of 1.2 kilobytes, why not use it?)
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How to style SVG with external CSS?
I have several SVG graphics I'd like to modify the colors of via my external style sheets - not directly within each SVG file. I'm not putting the graphics in-line, but storing them in my images folder and pointing to them.
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