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How do I test if a variable is a number in Bash?
... the regex appropriately; for instance:
^[0-9]+([.][0-9]+)?$
...or, to handle numbers with a sign:
^[+-]?[0-9]+([.][0-9]+)?$
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How can I apply a function to every row/column of a matrix in MATLAB?
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Many built-in operations like sum and prod are already able to operate across rows or columns, so you may be able to refactor the function you are applying to take advantage of this.
If that's not a viable option, one way to do it is to collect the rows or c...
Difference between save and saveAndFlush in Spring data jpa
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On saveAndFlush, changes will be flushed to DB immediately in this command. With save, this is not necessarily true, and might stay just in memory, until flush or commit commands are issued.
But be aware, that even if you flush th...
Do git tags get pushed as well?
...ectory all the tags are present, but when I logon to the
remote repository and do a git tag , only the first few show up.
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Indenting #defines
...re-ANSI C preprocessor did not allow for space between the start of a line and the "#" character; the leading "#" had to always be placed in the first column.
Pre-ANSI C compilers are non-existent these days. Use which ever style (space before "#" or space between "#" and the identifier) you prefer...
Command prompt won't change directory to another drive
I'm trying to compile some java (learning java currently), and to do so I need to change command-prompt's directory (using javac).
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Instantiate and Present a viewController in Swift
I started taking a look of the new Swift on Xcode 6 , and I tried some demo projects and tutorials. Now I am stuck at:
1...
A gentle tutorial to Emacs/Swank/Paredit for Clojure
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[Edit from non-author: this is from 2010, and the process has been significantly simplified since May 2011. I'll add a post to this answer with my setup notes as of Feb 2012.]
You'll need to put together a few pieces: Emacs, SLIME (which works perfectly well with Cl...
Execute AsyncTask several times
In my Activity I use a class which extends from AsyncTask and a parameter which is an instance of that AsyncTask. When I call mInstanceOfAT.execute("") everything is fine.
But the app crash when I press an update button which calls again the AsyncTask(In case the network job didnt work). Cause the...
Polymorphism with gson
... problem deserializing a json string with Gson.
I receive an array of commands. The command can be start, stop , some other type of command. Naturally I have polymorphism, and start/stop command inherit from command.
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