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Specifying rails version to use when creating a new application
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edited Sep 20 '11 at 16:23
Paweł Gościcki
7,05755 gold badges5555 silver badges7474 bronze badges
ans...
How to get row from R data.frame
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130
x[r,]
where r is the row you're interested in. Try this, for example:
#Add your data
x <...
How do I use raw_input in Python 3
I am using Python 3.1 and can't get the raw_input to "freeze" the dos pop-up. The book I'm reading is for Python 2.5 and I'm using Python 3.1
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Single Line Nested For Loops
...f the list comprehension (here (x,y)):
>>> [(x, y) for x in [1,2,3] for y in [3,1,4] if x != y]
[(1, 3), (1, 4), (2, 3), (2, 1), (2, 4), (3, 1), (3, 4)]
It's exactly the same as this nested for loop (and, as the tutorial says, note how the order of for and if are the same).
>>>...
Static variables in member functions
...e of i will remain through out the program. To add an example:
A o1, o2, o3;
o1.foo(); // i = 1
o2.foo(); // i = 2
o3.foo(); // i = 3
o1.foo(); // i = 4
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The difference between bracket [ ] and double bracket [[ ]] for accessing the elements of a list or
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336
The R Language Definition is handy for answering these types of questions:
http://cran.r-pro...
Select count(*) from multiple tables
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337
SELECT (
SELECT COUNT(*)
FROM tab1
) AS count1,
(
S...
PHP cURL not working - WAMP on Windows 7 64 bit
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309
Go to http://www.anindya.com/php-5-4-3-and-php-5-3-13-x64-64-bit-for-windows/ and download the...
How is a CRC32 checksum calculated?
Maybe I'm just not seeing it, but CRC32 seems either needlessly complicated, or insufficiently explained anywhere I could find on the web.
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How to compare two strings in dot separated version format in Bash?
...;
1) op='>';;
2) op='<';;
esac
if [[ $op != $3 ]]
then
echo "FAIL: Expected '$3', Actual '$op', Arg1 '$1', Arg2 '$2'"
else
echo "Pass: '$1 $op $2'"
fi
}
# Run tests
# argument table format:
# testarg1 testarg2 expected_relationship
ech...