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How to convert a data frame column to numeric type?

... and this is not the most confounding thing, but it can confuse you, especially if you read this before rolling into bed. Here goes: first two columns are character. I've deliberately called 2nd one fake_char. Spot the similarity of this character variable with one that Dirk created in his reply. I...
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Comparison of Lucene Analyzers

...text. For example, KeywordAnalyzer you mentioned doesn't split the text at all and takes all the field as a single token. At the same time, StandardAnalyzer (and most other analyzers) use spaces and punctuation as a split points. For example, for phrase "I am very happy" it will produce list ["i", "...
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When to choose checked and unchecked exceptions

...eople misunderstand what this means. Predictable but unpreventable: The caller did everything within their power to validate the input parameters, but some condition outside their control has caused the operation to fail. For example, you try reading a file but someone deletes it between the time ...
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When to make a type non-movable in C++11?

... Herb's answer (before it was edited) actually gave a good example of a type which shouldn't be movable: std::mutex. The OS's native mutex type (e.g. pthread_mutex_t on POSIX platforms) might not be "location invariant" meaning the object's address is part of its va...
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PHP Composer update “cannot allocate memory” error (using Laravel 4)

... you should be committing your composer.lock file and doing a composer install on a production environment which is less resource intensive. More details here: https://github.com/composer/composer/issues/1898#issuecomment-23453850 ...
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Private virtual method in C++

...d, without further exposing the virtual functions directly by making them callable by derived classes (as would be possible if the functions were just protected). The point is that virtual functions exist to allow customization; unless they also need to be invoked directly from within derived classe...
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How to copy DLL files into the same folder as the executable using CMake?

...the configuration type into the path to the dll in the add_custom_command call, like this: add_custom_command(TARGET MyTest POST_BUILD COMMAND ${CMAKE_COMMAND} -E copy_directory "${PROJECT_SOURCE_DIR}/libs/$<CONFIGURATION>" $<TARGET_FILE_DIR:MyTest>) ...
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Best practice to run Linux service as a different user

...ervices default to starting as root at boot time on my RHEL box. If I recall correctly, the same is true for other Linux distros which use the init scripts in /etc/init.d . ...
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Quickest way to compare two generic lists for differences

...2.Except(list1).ToList(); I suspect there are approaches which would actually be marginally faster than this, but even this will be vastly faster than your O(N * M) approach. If you want to combine these, you could create a method with the above and then a return statement: return !firstNotSecon...
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Cycles in family tree software

...this format contains some severe misconceptions about what a family tree really looks like. GEDCOM has many issues, such as incompatibility with same sex relations, incest, etc... Which in real life happens more often than you'd imagine (especially when going back in time to the 1700-1800). We hav...