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How to convert Nonetype to int or string?
...erally a number, but could be None . I want to divide it by a number, but Python raises:
10 Answers
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How to check if all of the following items are in a list?
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Operators like <= in Python are generally not overriden to mean something significantly different than "less than or equal to". It's unusual for the standard library does this--it smells like legacy API to me.
Use the equivalent and more clearl...
matplotlib Legend Markers Only Once
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I like to change my matplotlib rc parameters dynamically in every python script. To achieve this goal I simply use somthing like that at the beginning of my python files.
from pylab import *
rcParams['legend.numpoints'] = 1
This will apply to all plots generated from my python file.
EDI...
Why does (1 in [1,0] == True) evaluate to False?
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Python actually applies comparison operator chaining here. The expression is translated to
(1 in [1, 0]) and ([1, 0] == True)
which is obviously False.
This also happens for expressions like
a < b < c
which tran...
How to trick an application into thinking its stdout is a terminal, not a pipe
... is amazing. I needed this for an extremely rare use case with an embedded Python library within an executable that is run within Wine. When I ran in a terminal it worked but when I ran the .desktop file I created it would always crash because Py_Initialize didn't see proper stdin/stderr.
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What's so great about Lisp? [closed]
...You could in theory embed any language into Lisp like Rust, Ruby, C, Java, Python, Erlang. So the s-expression version of Python (Hy) and the of Rust is called (Risp) [although I don't know how stable these are]. If you write code in Hy instead of Python you have the ability of macros and structur...
How to extract the decision rules from scikit-learn decision-tree?
...at(indent, tree_.value[node])
recurse(0, 1)
This prints out a valid Python function. Here's an example output for a tree that is trying to return its input, a number between 0 and 10.
def tree(f0):
if f0 <= 6.0:
if f0 <= 1.5:
return [[ 0.]]
else: # if f0 > 1.5
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Detect if a NumPy array contains at least one non-numeric value?
... Why doesn't something like float('nan') in x not work? I tried it and python returns False where x = [1,2,3,float('nan')].
– Charlie Parker
Oct 13 '16 at 22:02
1
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Why doesn't Objective-C support private methods?
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More python being "obj-c-ic" :). Guido was quite proactive in maintaining Python on NeXT systems, including creating the 1st version of PyObjC. Thus, ObjC did influence python somewhat.
– bbum
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Set Django IntegerField by choices=… name
...es
super(models.IntegerField, self).__init__(**kwargs)
def to_python(self, value):
return self.val2choice[value]
def get_db_prep_value(self, choice):
return self.choice2val[choice]
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