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Switch statement fall-through…should it be allowed? [closed]
For as long as I can remember I have avoided using switch statement fall-through. Actually, I can't remember it ever entering my consciousness as a possible way to do things as it was drilled into my head early on that it was nothing more than a bug in the switch statement. However, today I ran acro...
How to programmatically send SMS on the iPhone?
Does anybody know if it's possible, and how, to programmatically send a SMS from the iPhone , with the official SDK / Cocoa Touch?
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How to list all the available keyspaces in Cassandra?
...y the schema_keyspaces table in the system keyspace. There's also a table called schema_columnfamilies which contains information about all tables.
The DESCRIBE and SHOW commands only work in cqlsh and cassandra-cli.
share
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How to reset a single table in rails?
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A lot of people (like me) come here to find how to delete all the data in the table. Here you go:
$ rails console
> ModelName.delete_all
or
> ModelName.destroy_all
destroy_all checks dependencies and callbacks, and takes a little longer.
delete_all is a straight SQL que...
Does Haskell require a garbage collector?
... the user types "clear"; so the lifetime of this must be determined dynamically, and this is why dynamic memory management is necessary.
So in this sense, automated dynamic memory allocation is necessary, and in practice this means: yes, Haskell requires a garbage collector, since garbage collectio...
Convert List to List
...iterate over the list and cast the elements. This can be done using ConvertAll:
List<A> listOfA = new List<C>().ConvertAll(x => (A)x);
You could also use Linq:
List<A> listOfA = new List<C>().Cast<A>().ToList();
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Split a vector into chunks in R
...ks of size 20:
split(d, ceiling(seq_along(d)/20))
More details: I think all you need is seq_along(), split() and ceiling():
> d <- rpois(73,5)
> d
[1] 3 1 11 4 1 2 3 2 4 10 10 2 7 4 6 6 2 1 1 2 3 8 3 10 7 4
[27] 3 4 4 1 1 7 2 4 6 0 5 7 4 6 8 4 7 1...
Split string with multiple delimiters in Python [duplicate]
...think there is. See my comment on your post below.
– alldayremix
Feb 21 '13 at 23:23
18
I'd prefe...
Elegant way to check for missing packages and install them?
...em are novice/intermediate R users and don't realize that they have to install packages they don't already have.
29 Answers...
Utilizing multi core for tar+gzip/bzip compression/decompression
I normally compress using tar zcvf and decompress using tar zxvf (using gzip due to habit).
6 Answers
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