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Ruby class instance variable vs. class variable
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Instance variable on a class:
class Parent
@things = []
def self.things
@things
end
def things
self.class.things
end
end
class Child < Parent
@things = []
end
Parent.things << :car
Child.things << :doll
mom = Parent.new
dad...
Fastest way to list all primes below N
This is the best algorithm I could come up.
35 Answers
35
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LINQ to SQL - Left Outer Join with multiple join conditions
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You need to introduce your join condition before calling DefaultIfEmpty(). I would just use extension method syntax:
from p in context.Periods
join f in context.Facts on p.id equals f.periodid into fg
from fgi in fg.Where(f => f.otherid == 17).DefaultIfEmpty()
where p.companyid == 100
sel...
How do you detect where two line segments intersect? [closed]
... determine whether or not two lines intersect, and if they do, at what x,y point?
27 Answers
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How to export and import a .sql file from command line with options? [duplicate]
Not Duplicate! looking for some feature have phpmyadmin during export in command line
8 Answers
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Principal component analysis in Python
I'd like to use principal component analysis (PCA) for dimensionality reduction. Does numpy or scipy already have it, or do I have to roll my own using numpy.linalg.eigh ?
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How to rename a file using Python
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Use os.rename:
import os
os.rename('a.txt', 'b.kml')
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How do I display the current value of an Android Preference in the Preference summary?
This must come up very often.
34 Answers
34
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How do I reset a sequence in Oracle?
In PostgreSQL , I can do something like this:
18 Answers
18
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Permutations in JavaScript?
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If you notice, the code actually splits the chars into an array prior to do any permutation, so you simply remove the join and split operation
var permArr = [],
usedChars = [];
function permute(input) {
var i, ch;
for (i = 0; i < input.len...