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Float vs Decimal in ActiveRecord
...esent a Float. It's like a scientific notation for binary (something like +1.43*10^2). Because of that, it is impossible to store fractions and decimals in Float exactly.
That's why there is a Decimal format. If you do this:
irb:001:0> "%.47f" % (1.0/10)
=> "0.100000000000000005551115123125...
Why is using the rails default_scope often recommend against?
...
193
Problem 1
Lets consider the basic example:
class Post < ActiveRecord::Base
default_sco...
How do you extract a column from a multi-dimensional array?
...
>>> import numpy as np
>>> A = np.array([[1,2,3,4],[5,6,7,8]])
>>> A
array([[1, 2, 3, 4],
[5, 6, 7, 8]])
>>> A[:,2] # returns the third columm
array([3, 7])
See also: "numpy.arange" and "reshape" to allocate memory
Example: (Allocating a ar...
What is the usefulness of PUT and DELETE HTTP request methods?
...…
For the full specification visit:
http://www.w3.org/Protocols/rfc2616/rfc2616-sec9.html
Since current browsers unfortunately do not support any other verbs than POST and GET in HTML forms, you usually cannot utilize HTTP to it's full extent with them (you can still hijack their submission ...
How to do a case sensitive search in WHERE clause (I'm using SQL Server)?
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177
Can be done via changing the Collation. By default it is case insensitive.
Excerpt from the l...
Most common way of writing a HTML table with vertical headers?
...in a table should contain an equal number of columns (TD). Your header has 1 while the body has 3. You should use the colspan attribute to fix that.
Reference: "The THEAD, TFOOT, and TBODY sections must contain the same number of columns." - Last paragraph of section 11.2.3.
With that being said, ...
When should I use a composite index?
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112
You should use a composite index when you are using queries that benefit from it. A composite ...
Data structure for loaded dice?
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119
You are looking for the alias method which provides a O(1) method for generating a fixed discr...
What does “Splats” mean in the CoffeeScript tutorial?
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199
The term "splat operator" comes from Ruby, where the * character (sometimes called the "splat"...