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Generic type conversion FROM string
...es" for another class. These properties simply have a name and a value. Ideally, what I would like is to be able to add typed properties, so that the "value" returned is always of the type that I want it to be.
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How to filter a dictionary according to an arbitrary condition function?
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And here is a good explanation why the function call dict() is slower than the constructor/literal syntax {} doughellmann.com/2012/11/…
– dorvak
Jul 10 '13 at 9:37
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In Django - Model Inheritance - Does it allow you to override a parent model's attribute?
...ld instances (at least,
not at the moment). If a base class has a field called author, you
cannot create another model field called author in any class that
inherits from that base class.
share
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Ruby send vs __send__
I understand the concept of some_instance.send but I'm trying to figure out why you can call this both ways. The Ruby Koans imply that there is some reason beyond providing lots of different ways to do the same thing. Here are the two examples of usage:
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Using node.js as a simple web server
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Simplest Node.js server is just:
$ npm install http-server -g
Now you can run a server via the following commands:
$ cd MyApp
$ http-server
If you're using NPM 5.2.0 or newer, you can use http-server without installing it with npx. This isn't recommended for u...
Get the name of the currently executing method
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Even better than my first answer you can use __method__:
class Foo
def test_method
__method__
end
end
This returns a symbol – for example, :test_method. To return the method name as a string, call __method__.to_s instead.
Note: This requires Ruby 1.8.7.
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Pandas percentage of total with groupby
... is a table of some kind, so 100 * x doesn't intuitively make sense (especially when some of the cells contain strings like AZ, ...).
– dhardy
Feb 6 '15 at 9:42
6
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What does “abstract over” mean?
...the similarities. We say that we abstract over the differences, but this really means we're integrating by the similarities.
For example, consider a program that takes the sum of the numbers 1, 2, and 3:
val sumOfOneTwoThree = 1 + 2 + 3
This program is not very interesting, since it's not very a...
Get a list of checked checkboxes in a div using jQuery
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Unnecessary call of constructor var selected = new Array();. Better (cheaper) with var selected = [];
– Pono
Mar 17 '14 at 22:45
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Selecting multiple columns in a pandas dataframe
...).
df1 = df[['a', 'b']]
Alternatively, if it matters to index them numerically and not by their name (say your code should automatically do this without knowing the names of the first two columns) then you can do this instead:
df1 = df.iloc[:, 0:2] # Remember that Python does not slice inclusive of...