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How do I check if a number is a palindrome?
...ler problems. When I solved it in Haskell I did exactly what you suggest, convert the number to a String. It's then trivial to check that the string is a pallindrome. If it performs well enough, then why bother making it more complex? Being a pallindrome is a lexical property rather than a mathe...
Grant execute permission for a user on all stored procedures in database?
...call grant execute on the new stored procedure:
IF EXISTS (SELECT * FROM sys.database_principals WHERE name = N'asp_net')
DROP USER asp_net
GO
IF EXISTS (SELECT * FROM sys.database_principals
WHERE name = N'db_execproc' AND type = 'R')
DROP ROLE [db_execproc]
GO
--Create a database role....
CR...
How to import a module given its name as string?
... can import a list of modules by doing this:
>>> moduleNames = ['sys', 'os', 're', 'unittest']
>>> moduleNames
['sys', 'os', 're', 'unittest']
>>> modules = map(__import__, moduleNames)
Ripped straight from Dive Into Python.
...
Fast permutation -> number -> permutation mapping algorithms
...lation w[k-1] = k! is easily proved by induction.)
The number we get from converting our sequence will then be the sum of s[k] * w[k], with k running from 0 to n-1. Here s[k] is the k'th (rightmost, starting at 0) element of the sequence. As an example, take our {1, 2, 0, 1, 0}, with the rightmost ...
how to convert from int to char*?
...
Also, you need 12 characters to convert a 32-bit integer to a nul-terminated base-10 representation. 10 isn't enough for -2147483647.
– Steve Jessop
Jun 1 '12 at 9:12
...
How do you set your pythonpath in an already-created virtualenv?
...e it in the site-packages directory. E.g.:
cd $(python -c "from distutils.sysconfig import get_python_lib; print(get_python_lib())")
echo /some/library/path > some-library.pth
The effect is the same as adding /some/library/path to sys.path, and remain local to the virtualenv setup.
...
What is the meaning of “POSIX”?
...ified by the IEEE, to clarify and make uniform the application programming interfaces (and ancillary issues, such as commandline shell utilities) provided by Unix-y operating systems. When you write your programs to rely on POSIX standards, you can be pretty sure to be able to port them easily amon...
Equivalent of LIMIT and OFFSET for SQL Server?
...
Another sample :
declare @limit int
declare @offset int
set @offset = 2;
set @limit = 20;
declare @count int
declare @idxini int
declare @idxfim int
select @idxfim = @offset * @limit
select @idxini = @idxfim - (@limit-1);
WITH paging AS
(
SE...
Converting int to bytes in Python 3
...s much more expensive, so never use lists when you can use tuples. You can convert bigger integers by using int.to_bytes(3, "little").
Initializing bytes with a given length makes sense and is the most useful, as they are often used to create some type of buffer for which you need some memory of gi...
Assign pandas dataframe column dtypes
... pd.to_timedelta and pd.to_numeric
(As mentioned below, no more "magic", convert_objects has been deprecated in 0.17)
df = pd.DataFrame({'x': {0: 'a', 1: 'b'}, 'y': {0: '1', 1: '2'}, 'z': {0: '2018-05-01', 1: '2018-05-02'}})
df.dtypes
x object
y object
z object
dtype: object
df
x ...