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A monad is just a monoid in the category of endofunctors, what's the problem?

...gt; Anything including Anything else. As my imagination jumps to Int -> String, it also includes Integer -> Maybe Int, or even Maybe Double -> Either String Int where a :: Maybe Double; b :: Either String Int. So the statement comes together as follows: functor scope :: f a -> g b ...
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Benchmarking (python vs. c++ using BLAS) and (numpy)

...e python for my program, what could I do to increase the performance when calling BLAS or LAPACK routines? Make sure that numpy uses optimized version of BLAS/LAPACK libraries on your system. share | ...
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Can unit testing be successfully added into an existing production project? If so, how and is it wor

...lexity. No, tests don't write themselves, and, yes, it will take a little extra time to get things out the door. But in the long run it will take more time and cost more money to fix bugs after the fact than write tests up front. Period. That's all there is to it. ...
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Including all the jars in a directory within the Java classpath

... class path foo/* is expanded into foo/a.jar;foo/b.jar;foo/c.jar, and that string would be the value of the system property java.class.path. The CLASSPATH environment variable is not treated any differently from the -classpath (or -cp) command-line option. That is, wildcards are honored in all these...
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Difference between dispatch_async and dispatch_sync on serial queue?

... I do mean serial execution. In point of view that all tasks are executed serial regards to other tasks in the same queue. Of cause it still can be concurrent regards to other queues. It is the whole point of GCD that tasks can be dispatched and executed concurrently. ...
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Redirecting Output from within Batch file

... good and fast way that only opens and positions the file once @echo off call :sub >output.txt exit /b :sub command1 command2 ... commandN Edit 2020-04-17 Every now and then you may want to repeatedly write to two or more files. You might also want different messages on the screen. It is sti...
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pytest: assert almost equal

... I noticed that this question specifically asked about py.test. py.test 3.0 includes an approx() function (well, really class) that is very useful for this purpose. import pytest assert 2.2 == pytest.approx(2.3) # fails, default is ± 2.3e-06 assert 2.2 == pyte...
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How can I do division with variables in a Linux shell?

...tor in case statements than it can't resolve it. In that case use simple strings like div or devide or something else. See the code share | improve this answer | follow ...
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Saving enum from select in Rails 4.1

... What if an Invalid String is sent such as "ERROR_JUNK_Submission". Obviously there is no enum value such as this, and an exception is thrown. Where would we catch it? – FlyingV Nov 30 '15 at 19:54 ...
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Uninstall Node.JS using Linux command line?

How do you uninstall node.js using the cmd line in linux? 14 Answers 14 ...