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How to thoroughly purge and reinstall postgresql on ubuntu? [closed]
...nstall postgresql
or for a complete install:
apt-get install postgresql-8.4 postgresql-contrib-8.4 postgresql-doc-8.4
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How to convert char to int?
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285
I'm surprised nobody has mentioned the static method built right into System.Char...
int val =...
Rank function in MySQL
...erson VALUES (5, 'Nick', 22, 'M');
INSERT INTO person VALUES (6, 'Kathy', 18, 'F');
INSERT INTO person VALUES (7, 'Steve', 36, 'M');
INSERT INTO person VALUES (8, 'Anne', 25, 'F');
Result:
+------------+------+--------+------+
| first_name | age | gender | rank |
+------------+------+--------+--...
Regular expression to check if password is “8 characters including 1 uppercase letter, 1 special cha
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answered Feb 28 '12 at 7:32
npintinpinti
49.3k55 gold badges6464 silver badges8989 bronze badges
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Transpose list of lists
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How about
map(list, zip(*l))
--> [[1, 4, 7], [2, 5, 8], [3, 6, 9]]
For python 3.x users can use
list(map(list, zip(*l)))
Explanation:
There are two things we need to know to understand what's going on:
The signature of zip: zip(*iterables) This means zip expects an arb...
UTF-8: General? Bin? Unicode?
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In general, utf8_general_ci is faster than utf8_unicode_ci, but less correct.
Here is the difference:
For any Unicode character set, operations performed using the _general_ci collation are faster than those for the _unicode_ci collati...
efficient circular buffer?
... d.append(i)
...
>>> d
deque([10, 11, 12, 13, 14, 15, 16, 17, 18, 19], maxlen=10)
There is a recipe in the docs for deque that is similar to what you want. My assertion that it's the most efficient rests entirely on the fact that it's implemented in C by an incredibly skilled crew that...
Pandas index column title or name
...ex via its name property
In [7]: df.index.name
Out[7]: 'Index Title'
In [8]: df.index.name = 'foo'
In [9]: df.index.name
Out[9]: 'foo'
In [10]: df
Out[10]:
Column 1
foo
Apples 1
Oranges 2
Puppies 3
Ducks 4
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How can I change Mac OS's default Java VM returned from /usr/libexec/java_home
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89
I think JAVA_HOME is the best you can do. The command-line tools like java and javac will resp...
How do I make a matrix from a list of vectors in R?
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[6,] 6 1 2 3 4 5
[7,] 7 1 2 3 4 5
[8,] 8 1 2 3 4 5
[9,] 9 1 2 3 4 5
[10,] 10 1 2 3 4 5
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