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Is System.nanoTime() completely useless?
...cific counter. Now consider the following case I use to measure time of a call:
15 Answers
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Disable messages upon loading a package
...y R script is being used for further analysis I want to completely disable all of this output. How do I do that? Furthermore, I'd prefer to do it without having to modify ROCR at all, so that future users of this script don't have to do that either.
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MySQL Cannot Add Foreign Key Constraint
...storyID is an INT, Patient.MedicalHistory also needs to be an INT, not a SMALLINT.
Also, you should run the query set foreign_key_checks=0 before running the DDL so you can create the tables in an arbitrary order rather than needing to create all parent tables before the relevant child tables.
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How to get Maven project version to the bash command line
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I'm removing all logging (INFO,WARNING,etc) and 'Download' messages with mvn org.apache.maven.plugins:maven-help-plugin:2.1.1:evaluate -Dexpression=project.version|grep -Ev '(^\[|Download\w+:)'
– Chadwick
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What is the preferred syntax for defining enums in JavaScript?
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This isn't much of an answer, but I'd say that works just fine, personally
Having said that, since it doesn't matter what the values are (you've used 0, 1, 2), I'd use a meaningful string in case you ever wanted to output the current value.
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Turning off some legends in a ggplot
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You can use guide=FALSE in scale_..._...() to suppress legend.
For your example you should use scale_colour_continuous() because length is continuous variable (not discrete).
(p3 <- ggplot(mov, aes(year, rating, colour = length, shape = mpaa)) +
sca...
Fastest way to implode an associative array with keys
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I wonder if this is really the fastest way for the general question. There is some encoding going on in this function. So, if it's not for a URL, is this really faster than array_walk and what if you don't want it encoded?
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Difference between Destroy and Delete
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Basically destroy runs any callbacks on the model while delete doesn't.
From the Rails API:
ActiveRecord::Persistence.delete
Deletes the record in the database and freezes this instance to reflect that no changes should be ...
Getting an “ambiguous redirect” error
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Bash can be pretty obtuse sometimes.
The following commands all return different error messages for basically the same error:
$ echo hello >
bash: syntax error near unexpected token `newline`
$ echo hello > ${NONEXISTENT}
bash: ${NONEXISTENT}: ambiguous redirect
$ echo hello ...
Why is the minimalist, example Haskell quicksort not a “true” quicksort?
... two beautiful aspects:
Divide and conquer: break the problem into two smaller problems.
Partition the elements in-place.
The short Haskell example demonstrates (1), but not (2). How (2) is done may not be obvious if you don't already know the technique!
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