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Is it possible to specify condition in Count()?
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13 Answers
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Why is using the rails default_scope often recommend against?
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193
Problem 1
Lets consider the basic example:
class Post < ActiveRecord::Base
default_sco...
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...
How do I get a human-readable file size in bytes abbreviation using .NET?
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19 Answers
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How to pass parameters to a partial view in ASP.NET MVC?
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edited Oct 29 '13 at 15:01
Michał Powaga
19.7k66 gold badges4444 silver badges6060 bronze badges
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Hash Map in Python
...dictionary is a built-in type that supports key-value pairs.
streetno = {"1": "Sachin Tendulkar", "2": "Dravid", "3": "Sehwag", "4": "Laxman", "5": "Kohli"}
as well as using the dict keyword:
streetno = dict({"1": "Sachin Tendulkar", "2": "Dravid"})
or:
streetno = {}
streetno["1"] = "Sachin ...
What is the usefulness of PUT and DELETE HTTP request methods?
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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 ...
Change the name of a key in dictionary
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15 Answers
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How do you extract a column from a multi-dimensional array?
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>>> 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...