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Returning the product of a list
...sing lambda:
from operator import mul
reduce(mul, list, 1)
it is better and faster. With python 2.7.5
from operator import mul
import numpy as np
import numexpr as ne
# from functools import reduce # python3 compatibility
a = range(1, 101)
%timeit reduce(lambda x, y: x * y, a) # (1)
%timeit r...
Entity Framework VS LINQ to SQL VS ADO.NET with stored procedures? [closed]
...ork ("EF") - it now generates much better SQL (more like Linq to SQL does) and is easier to maintain and more powerful than Linq to SQL ("L2S"). As of the release of .NET 4.0, I consider Linq to SQL to be an obsolete technology. MS has been very open about not continuing L2S development further.
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How do I trim whitespace from a string?
How do I remove leading and trailing whitespace from a string in Python?
12 Answers
12...
iphone/ipad: How exactly use NSAttributedString?
Yes, many people are saying about Rich Text in iPhone/iPad and many knows about NSAttributedString .
9 Answers
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What are “signed” cookies in connect/expressjs?
...igure out what "signed cookies" actually are.
There isn't much on the net, and if I try this:
4 Answers
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When should I use Memcache instead of Memcached?
It seems that PHP has two memcached libraries named memcache and memcached . What is the difference and how do you know which one to use? Is one outdated? It seems that memcached offers more methods so I would assume that means it has had the most development - but it also seems to require exter...
Difference between jQuery’s .hide() and setting CSS to display: none
...er than writing out .css("display", "none") , but what’s the difference and what are both of them actually doing to the HTML element?
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What does the (unary) * operator do in this Ruby code?
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The * is the splat operator.
It expands an Array into a list of arguments, in this case a list of arguments to the Hash.[] method. (To be more precise, it expands any object that responds to to_ary/to_a, or to_a in Ruby 1.9.)
To illustrate, the following two ...
Database Structure for Tree Data Structure
...o-nested-sets
There are other models as well, including materialized path and nested sets:
http://communities.bmc.com/communities/docs/DOC-9902
Joe Celko has written a book on this subject, which is a good reference from a general SQL perspective (it is mentioned in the nested set article link abo...
Drop unused factor levels in a subsetted data frame
...t, so the mydf <- droplevels(mydf) solution suggested by Roman Luštrik and Tommy O'Dell below is preferable.
– Johan
May 9 '14 at 10:41
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