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Minimizing NExpectation for a custom distribution in Mathematica
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As far as I see, the problem is (as you already wrote), that MeanResidualLife takes a long time to compute, even for a single evaluation. Now, the FindMinimum or similar functions try to find a minimum to the function. Finding a minimum requires either to set the first derivative of the function...
python: how to identify if a variable is an array or a scalar
I have a function that takes the argument NBins . I want to make a call to this function with a scalar 50 or an array [0, 10, 20, 30] . How can I identify within the function, what the length of NBins is? or said differently, if it is a scalar or a vector?
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How to automatically generate N “distinct” colors?
I wrote the two methods below to automatically select N distinct colors. It works by defining a piecewise linear function on the RGB cube. The benefit of this is you can also get a progressive scale if that's what you want, but when N gets large the colors can start to look similar. I can also imagi...
How to efficiently compare two unordered lists (not sets) in Python?
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For short lists, big-O analysis is usually irrelevant because the timings are dominated by constant factors. For the longer lists, I suspect something is wrong with your benchmarking. For 100 ints with 5 repeats each, I get: 127 usec for sorted and 42 for Count...
Extract value of attribute node via XPath
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With xqilla it was necessary to call xs:string. I wonder why.
– krlmlr
Jul 22 '13 at 20:00
1
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How do I replace whitespaces with underscore?
...s, such as \t or a non-breaking space.
– Roberto Bonvallet
Jun 17 '09 at 15:49
13
Yes you are cor...
undefined reference to boost::system::system_category() when compiling
...raries. I have the 1.46-dev Boost libraries from the Ubuntu Repository installed, but I get an error when compiling the program.
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How to redirect to a 404 in Rails?
...ou want to show a 404 page, create a render_404 method (or not_found as I called it) in ApplicationController like this:
def not_found
raise ActionController::RoutingError.new('Not Found')
end
Rails also handles AbstractController::ActionNotFound, and ActiveRecord::RecordNotFound the same way....
What does 'super' do in Python?
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What's the difference?
SomeBaseClass.__init__(self)
means to call SomeBaseClass's __init__. while
super(Child, self).__init__()
means to call a bound __init__ from the parent class that follows Child in the instance's Method Resolution Order (MRO).
If the instance is a subclass of ...
Is it possible to forward-declare a function in Python?
...rwards is impossible, what about defining it in some other module?
Technically you still define it first, but it's clean.
You could create a recursion like the following:
def foo():
bar()
def bar():
foo()
Python's functions are anonymous just like values are anonymous, yet they can be ...