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Error: could not find function … in R
...the name of your function correctly? Names are case sensitive.
Did you install the package that contains the function? install.packages("thePackage") (this only needs to be done once)
Did you attach that package to the workspace ?
require(thePackage) or library(thePackage) (this should be done ever...
How to loop over directories in Linux?
I am writing a script in bash on Linux and need to go through all subdirectory names in a given directory. How can I loop through these directories (and skip regular files)?
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How can I declare and use Boolean variables in a shell script?
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if [ "$the_world_is_flat" = true ] ; then
echo 'Be careful not to fall off!'
fi
Original Answer
Caveats: https://stackoverflow.com/a/21210966/89391
the_world_is_flat=true
# ...do something interesting...
if $the_world_is_flat ; then
echo 'Be careful not to fall off!'
fi
From: Usi...
Suppress command line output
... invocation to this:
taskkill /im "test.exe" /f >nul 2>&1
and all will be better.
That works because stdout is file descriptor 1, and stderr is file descriptor 2 by convention. (0 is stdin, incidentally.) The 2>&1 copies output file descriptor 2 from the new value of 1, which wa...
Global variables in AngularJS
...lue. The problem with it is that the controller that initialises it, gets called again by angular some how and then resets the variable back to its initial value.
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What is the difference between async.waterfall and async.series
... https://github.com/caolan/async provides 2 similar methods, async.waterfall and async.series .
4 Answers
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Browser statistics on JavaScript disabled [closed]
I am having a hard time collecting publically available statistics on the percentage of web users that browse with JavaScript disabled.
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Delete newline in Vim
...wline. You can also combine this with a count, so pressing 3J will combine all 3 lines together.
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Mongoose indexing in production code
...dex in production. Once the index has been added, subsequent ensureIndex calls will simply see that the index already exists and then return. So it only has an effect on performance when you're first creating the index, and at that time the collections are often empty so creating an index would be...
Playing .mp3 and .wav in Java?
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this isnt working for me at all. it says that the imports do not exist. and i am running java 7...
– PulsePanda
Nov 26 '12 at 3:09
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