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Why is rbindlist “better” than rbind?
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rbindlist is an optimized version of do.call(rbind, list(...)), which is known for being slow when using rbind.data.frame
Where does it really excel
Some questions that show where rbindlist shines are
Fast vectorized merge of list of data.frames by row
Trouble...
Is there an equivalent to 'continue' in a Parallel.ForEach?
I am porting some code to Parallel.ForEach and got an error with a continue I have in the code. Is there something equivalent I can use in a Parallel.ForEach functionally equivalent to continue in a foreach loop?
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Ruby Arrays: select(), collect(), and map()
...following:
details.select{ |item| item[:qty] != "" }
That will give you all items where the :qty key isn't an empty string.
official select documentation
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Case insensitive Query with Spring CrudRepository
...meContainingIgnoreCase(String name);
}
See documentation for a list of all supported keywords inside method names.
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In absence of preprocessor macros, is there a way to define practical scheme specific flags at proje
... The simplest example is the DEBUG=1 macro that is defined by default for all Xcode projects in the default scheme for the Run build. One could query #ifdef DEBUG ... and make decisions in the code accordingly, even compiling out non-necessary code.
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What do @, - and + do as prefixes to recipe lines in Make?
...cuted.
- means ignore the exit status of the command that is executed (normally, a non-zero exit status would stop that part of the build).
+ means 'execute this command under make -n' (or 'make -t' or 'make -q') when commands are not normally executed. See also the POSIX specification for make and ...
Oracle “(+)” Operator
..."adding NULL values if no match found". For example, "a.id=b.id(+)" means allow b.id to be NULL if there is no match with a.id.
– beach
Oct 26 '10 at 5:00
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What does gcc's ffast-math actually do?
...tside of IEEE standards, but I can't seem to find information on what is really happening when it's on. Can anyone please explain some of the details and maybe give a clear example of how something would change if the flag was on or off?
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Change directory command in Docker?
... && \
rm -f treeio.zip && cd treeio && pip install -r requirements.pip
Because of the use of '&&', it will only get to the final 'pip install' command if all the previous commands have succeeded.
In fact, since every RUN creates a new commit & (currently) a...
Git merge left HEAD marks in my files
...ess of merging, but there were some parts that Git couldn't merge automatically. You'll need to hand-edit those parts to what you want them to be and then commit the results.
For instance, in your particular case, you'd probably want to resolve it like this (note - the arrows/text on the right ar...