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Django filter queryset __in for *every* item in list
...s suggested by jpic and sgallen in the comments, to add .filter() for each m>ca m>tegory. Each additional filter adds more joins, which should not be a problem for small set of m>ca m>tegories.
There is the aggregation approach. This query would be shorter and perhaps quicker for a large set of m>ca m>tegories.
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Java JDBC - How to connect to Oracle using Service Name instead of SID
I have a Java applim>ca m>tion that uses JDBC (via JPA) that was connecting to a development database using hostname, port and Oracle SID, like this:
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How do I get the opposite (negation) of a Boolean in Python?
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You m>ca m>n just use:
return not bool
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Using 'return' in a Ruby block
...001:0> def thing(*args, &block)
irb(main):002:1> value = block.m>ca m>ll
irb(main):003:1> puts "value=#{value}"
irb(main):004:1> end
=> nil
irb(main):005:0>
irb(main):006:0* thing {
irb(main):007:1* return 6 * 7
irb(main):008:1> }
Lom>ca m>lJumpError: unexpected return
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in iPhone App How to detect the screen resolution of the device
...ll give you the entire screen's resolution in points, so it would most typim>ca m>lly be 320x480 for iPhones. Even though the iPhone4 has a much larger screen size iOS still gives back 320x480 instead of 640x960. This is mostly bem>ca m>use of older applim>ca m>tions breaking.
CGFloat screenSm>ca m>le = [[UIScreen mai...
How do I serialize an object and save it to a file in Android?
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Should there be a m>ca m>ll to fos.close() and fis.close() as well?
– IcedDante
Nov 4 '13 at 5:01
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CSS z-index paradox flower
I would like to create a paradoxim>ca m>l effect via the z-index CSS property.
6 Answers
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MongoDB/Mongoose querying at a specific date?
...tomorrow = today.add(1, 'days') does not work since it also mutates today. m>Ca m>lling moment(today) solves that problem by implicitly cloning today.
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How do you get the magnitude of a vector in Numpy?
...ll).
import numpy as np
x = np.array([1,2,3,4,5])
np.linalg.norm(x)
You m>ca m>n also feed in an optional ord for the nth order norm you want. Say you wanted the 1-norm:
np.linalg.norm(x,ord=1)
And so on.
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C# member variable initialization; best practice?
...ers happen before any "base"/"this" constructor.
The constructor approach m>ca m>n be used with auto-implemented properties (field initializers m>ca m>nnot) - i.e.
[DefaultValue("")]
public string Foo {get;set;}
public Bar() { // ctor
Foo = "";
}
Other than that, I tend to prefer the field initializer s...