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Is there a TRY CATCH command in Bash
... writing a shell script and need to check that a terminal app has been installed. I want to use a TRY/CATCH command to do this unless there is a neater way.
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Simultaneously merge multiple data.frames in a list
...ch data.frame differs in terms of the number of rows and columns, but they all share the key variables (which I've called "var1" and "var2" in the code below). If the data.frames were identical in terms of columns, I could merely rbind , for which plyr's rbind.fill would do the job, but that'...
A JRE or JDK must be available in order to run Eclipse. No JVM was found after searching the followi
...st nailed down the root cause on my own Windows machine. The GlassFish installer complained with exactly the same error message and after digging in GlassFish forums, the cause was clear: a corrupt JRE install on a Windows machine. My JRE came along with the JDK and the Java 6 JDK installer didn't i...
namedtuple and default values for optional keyword arguments
...lds)
>>> Node()
Node(val=None, left=None, right=None)
Order
In all versions of Python, if you set fewer default values than exist in the namedtuple, the defaults are applied to the rightmost parameters. This allows you to keep some arguments as required arguments.
>>> Node.__ne...
How do I find where an exception was thrown in C++?
I have a program that throws an uncaught exception somewhere. All I get is a report of an exception being thrown, and no information as to where it was thrown. It seems illogical for a program compiled to contain debug symbols not to notify me of where in my code an exception was generated.
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~x + ~y == ~(x + y) is always false?
...=> -1 == -2
Hence, a contradiction. Therefore, ~(x+y) != ~x + ~y for all x and y (mod 2n).
*It is interesting to note that on a machine with one's complement arithmetic, the equality actually holds true for all x and y. This is because under one's complement, ~x = -x. Thus, ~x + ~y == -x + ...
Django: How to completely uninstall a Django app?
What is the procedure for completely uninstalling a Django app, complete with database removal?
5 Answers
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What is the best way to check for Internet connectivity using .NET?
...google.com does not return some HTML :)
– Daniel Vassallo
Jan 9 '10 at 1:01
3
@Daniel: true on th...
Determining Referer in PHP
...s the most reliable and secure way to determine what page either sent, or called (via AJAX), the current page. I don't want to use the $_SERVER['HTTP_REFERER'] , because of the (lack of) reliability, and I need the page being called to only come from requests originating on my site.
Edit: I am...
Complete Working Sample of the Gmail Three-Fragment Animation Scenario?
...at I'll refer to as "the Gmail three-fragment animation" scenario. Specifically, we want to start with two fragments, like this:
...