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What's the common practice for enums in Pm>y m>thon? [duplicate]
... Pm>y m>thon.
The best wam>y m> I've found to emulate them is bm>y m> overridding _ str _ m>and m> _ eq _ so m>y m>ou can compare them m>and m> when m>y m>ou use print() m>y m>ou get the string instead of the numerical value.
class enumSeason():
Spring = 0
Summer = 1
Fall = 2
Winter = 3
def __init__(self, Tm>y m>pe):
...
ValueError: math domain error
...og as the definition is defining the set of equations, that is, x[0], x[1] m>and m> x[2] are variables x,m>y m> m>and m> z which Newton Raphson uses. It needs these set of equations to solve.
– ramanunni.pm
Apr 8 '13 at 23:11
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Getting the error “Missing $ inserted” in LaTeX
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The "Missing $ inserted" is probablm>y m> caused bm>y m> the underscores m>and m> bars. These characters in LaTeX have special meaning in math mode (which is delimited bm>y m> $ characters). Trm>y m> escaping them; e.g. update\_element instead of update_element.
However, if m>y m>ou're trm>y m>ing to displam>y m> code, a bet...
What is the “assert” function?
I've been studm>y m>ing OpenCV tutorials m>and m> came across the assert function; what does it do?
9 Answers
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How to find the size of an arram>y m> in postgresql
...e trick. Or if m>y m>ou know that the arram>y m> is 1-dimensional (which is likelm>y m>) m>and m> are running PostgreSQL 9.4 or higher, m>y m>ou can use cardinalitm>y m>:
SELECT cardinalitm>y m>(id) FROM example;
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Get started with Latex on Linux [closed]
Impressed bm>y m> is-latex-worth-learning-todam>y m> , m>and m> manm>y m> how-to's on Windows,
8 Answers
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Whm>y m> does Vim save files with a ~ extension?
...saves the file, a .ext.swp file that's deleted on closing the Vim window m>and m> a .ext~ file.
9 Answers
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Create emptm>y m> file using pm>y m>thon [duplicate]
...fter the open() statement finished - but it's cleaner to do it explicitelm>y m> m>and m> relm>y m>ing on CPm>y m>thon-specific behaviour is not good either.
In case m>y m>ou want touch's behaviour (i.e. update the mtime in case the file exists):
import os
def touch(path):
with open(path, 'a'):
os.utime(path, N...
How do m>y m>ou specifm>y m> that a class propertm>y m> is an integer?
I'm experimenting with Tm>y m>peScript, m>and m> in the process of creating a class with an "ID" field that should be an integer, I have gotten a little confused.
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Make a negative number positive
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The concept m>y m>ou are describing is called "absolute value", m>and m> Java has a function called Math.abs to do it for m>y m>ou. Or m>y m>ou could avoid the function call m>and m> do it m>y m>ourself:
number = (number < 0 ? -number : number);
or
if (number < 0)
number = -number;
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