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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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Weighted random numbers
...a weighted random numbers. I'm currently just banging my head against the wall and cannot figure this out.
7 Answers
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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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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...
Change all files and folders permissions of a directory to 644/755
How would I change all files to 644 and all folders to 755 using chmod from the linux command prompt? (Terminal)
8 Answ...
Odd behavior when Java converts int to byte?
...+ unsignedByte);
Would print out: "Signed: -1 Unsigned: 255"
What's actually happening here?
We are using bitwise AND to mask all of the extraneous sign bits (the 1's to the left of the least significant 8 bits.)
When an int is converted into a byte, Java chops-off the left-most 24 bits
111111...
uint8_t vs unsigned char
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It documents your intent - you will be storing small numbers, rather than a character.
Also it looks nicer if you're using other typedefs such as uint16_t or int32_t.
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When would anyone use a union? Is it a remnant from the C-only days?
I have learned but don't really get unions. Every C or C++ text I go through introduces them (sometimes in passing), but they tend to give very few practical examples of why or where to use them. When would unions be useful in a modern (or even legacy) case? My only two guesses would be programming ...
How to change the CHARACTER SET (and COLLATION) throughout a database?
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Do you really need to use "ALTER TABLE <table_name> MODIFY <column_name> ...". According to dev.mysql.com/doc/refman/5.5/en/alter-table.html it seems "ALTER TABLE <table_name> CONVERT TO CHARACTER SET ..." also chan...
What's the difference between django OneToOneField and ForeignKey?
...Guide to Django:
OneToOneField
A one-to-one relationship. Conceptually, this is similar to a ForeignKey with unique=True, but the "reverse" side of the relation will directly return a single object.
In contrast to the OneToOneField "reverse" relation, a ForeignKey "reverse" relation retur...