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How are feature_importances in RandomForestClassifier determined?
...d in [1] (often cited, but unfortunately rarely read...). It is sometimes called "gini importance" or "mean decrease impurity" and is defined as the total decrease in node impurity (weighted by the probability of reaching that node (which is approximated by the proportion of samples reaching that no...
Redirecting stdout to “nothing” in python
...
A nice way to do this is to create a small context processor that you wrap your prints in. You then just use is in a with-statement to silence all output.
Python 2:
import os
import sys
from contextlib import contextmanager
@contextmanager
def silence_stdout():
...
How do you 'redo' changes after 'undo' with Emacs?
...ven a navigation command such as C-f) after a sequence of undo operations, all the undos are pushed on to the operation stack. So the next undo undoes the last command. Suppose you do have an operation sequence that looks like this:
Insert "foo"
Insert "bar"
Insert "I love spam"
Now, you undo....
What is the most efficient string concatenation method in python?
... idiomatic and thus easier for other python programmers to understand.
Finally, the golden rule of optimization: don't optimize unless you know you need to, and measure rather than guessing.
You can measure different methods using the timeit module. That can tell you which is fastest, instead of r...
Why is it string.join(list) instead of list.join(string)?
...
I do not agree conceptually even if It makes sense codewise. list.join(string) appears more an object-oriented approach whereas string.join(list) sounds much more procedural to me.
– Eduardo Pignatelli
Jan 14 ...
Proper Repository Pattern Design in PHP?
...te a complete example of a basic controller for viewing and editing Users.
All code must be fully testable and mockable.
The controller should have no idea where the data is stored (meaning it can be changed).
Example to show a SQL implementation (most common).
For maximum performance, controllers s...
What does “mro()” do?
...very attribute you get on a class's instance, not just methods, is conceptually looked up along the __mro__, so, if more than one class among the ancestors defines that name, this tells you where the attribute will be found -- in the first class in the __mro__ that defines that name.
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Error handling in Bash
...kens code's predictability and portability).
You can either let the trap call error for you (in which case it uses the default exit code of 1 and no message) or call it yourself and provide explicit values; for instance:
error ${LINENO} "the foobar failed" 2
will exit with status 2, and give an ...
Run function from the command line
...ral answer. I have a script defined multiple customer functions, and only call one depending on my need
– xappppp
Apr 15 '18 at 4:16
1
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How can I save a screenshot directly to a file in Windows? [closed]
...ormat format = ImageFormat.PNG; or ImageFormat format = ImageFormat.JPG; All is here for you
– Patrick Desjardins
Oct 1 '08 at 15:31
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