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Python: split a list based on a condition?
What's the best way, both aesthetically and from a performance perspective, to split a list of items into multiple lists based on a conditional? The equivalent of:
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Counting the Number of keywords in a dictionary in python
... the len() function.
> a = {'foo':42, 'bar':69}
> len(a)
2
To get all the distinct words (i.e. the keys), use the .keys() method.
> list(a.keys())
['foo', 'bar']
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Matplotlib (pyplot) savefig outputs blank image
...values that depend whether or not T0 exists.
Second, after plt.show() is called, a new figure is created. To deal with this, you can
Call plt.savefig('tessstttyyy.png', dpi=100) before you call plt.show()
Save the figure before you show() by calling plt.gcf() for "get current figure", then you ca...
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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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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Are JavaScript strings immutable? Do I need a “string builder” in JavaScript?
...ved would be the fastest way, though I kept thinking that adding a method call may make it slower...
function StringBuilder() {
this._array = [];
this._index = 0;
}
StringBuilder.prototype.append = function (str) {
this._array[this._index] = str;
this._index++;
}
StringBuilder.pro...
ASP.NET Web API - PUT & DELETE Verbs Not Allowed - IIS 8
...tly upgraded from Visual Studio 2010 to the Visual Studio 2012 RC. The installer also installs IIS 8 Express which Visual Studio now uses as the default web server.
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Refresh a page using PHP
How can I refresh a page using PHP periodically? If I can not do it by PHP, what is the best recommended scenario?
13 Answe...
Is it possible to use “/” in a filename?
...hould ever be done, but is there a way to use the slash character that normally separates directories within a filename in Linux?
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Docker how to change repository name or rename image?
...host OS and Docker version? I suspect that something about your Docker installation is modifying the tag instruction.
– Andy
Feb 18 '16 at 2:41
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