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When to use os.name, sys.platform, or platform.system?
...ommended to use if sys.platform.startswith('linux') idiom because "linux2" means a Linux kernel version 2.xx or 3. Older kernels are currently never used. In Python 3.3 are all Linux systems simple 'linux'.
I do not know the specifics of "Mac" and "Java" systems and so I can not use the results o...
Javascript: Extend a Function
...
But there are such better ways to do that. Like for instance, providing a means of registering init functions.
// In main.js
var MyLibrary = (function() {
var publicSymbols = {},
initfunctions = [];
publicSymbols.init = init;
function init() {
var funcs = initFunctions...
What is global::?
...nce of the class from within another namespace whereby you defined another meaning for Foo, it would take the most local scoped. See the edit
– chrisw
Feb 22 '13 at 11:19
add ...
filter items in a python dictionary where keys contain a specific string
...y maintainable. Just because you can write it out in a single line doesn't mean that you should. Your existing solution is close to what I would use other than I would user iteritems to skip the value lookup, and I hate nested ifs if I can avoid them:
for key, val in d.iteritems():
if filter_st...
What is the most efficient way to store tags in a database?
...ome the many-to-many obstacle.
Something like:
Table: Items
Columns: Item_ID, Item_Title, Content
Table: Tags
Columns: Tag_ID, Tag_Title
Table: Items_Tags
Columns: Item_ID, Tag_ID
It might be that your web app is very very popular and need de-normalizing down the road, but it's pointless muddy...
How to concatenate strings of a string field in a PostgreSQL 'group by' query?
... asked for, even letting you specify the delimiter string:
SELECT company_id, string_agg(employee, ', ')
FROM mytable
GROUP BY company_id;
Postgres 9.0 also added the ability to specify an ORDER BY clause in any aggregate expression; otherwise, the order is undefined. So you can now write:
SELEC...
How to detect if a stored procedure already exists
... After that, you can ALTER the stored procedure to your liking.
IF object_id('YourSp') IS NULL
EXEC ('create procedure dbo.YourSp as select 1')
GO
ALTER PROCEDURE dbo.YourSp
AS
...
This way, security settings, comments and other meta deta will survive the deployment.
...
What does a colon following a C++ constructor name do? [duplicate]
...ctor's implementation.
The constructor's signature is:
MyClass();
This means that the constructor can be called with no parameters. This makes it a default constructor, i.e., one which will be called by default when you write MyClass someObject;.
The part : m_classID(-1), m_userdata(0) is call...
Find integer index of rows with NaN in pandas dataframe
...:].index
And their corresponding timings:
333 µs ± 9.95 µs per loop (mean ± std. dev. of 7 runs, 1000 loops each)
280 µs ± 220 ns per loop (mean ± std. dev. of 7 runs, 1000 loops each)
313 µs ± 128 ns per loop (mean ± std. dev. of 7 runs, 1000 loops each)
6.84 ms ± 1.59 µs per loop (m...
Sqlite primary key on multiple columns
...ent, it is an error." Yes, the railroad diagrams might indicate that is valid as well, but the text below clarifies that it is not.
– Brian Campbell
Mar 23 '11 at 19:03
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