Re: [Matplotlib-users] Re: matplotlib.mlab.find() not quite like Matlab"s

[Chris B. <Chr...@no...>]

Darren Dale wrote:
>  >I guess there is no way in Python of emulating
>  >Matlab"s detection of the number of output arguments.
> 
> I just got a response from c.l.p. Somebody remembered seeing this at ASPN:
> http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/284742
> 
> expecting() is the workhorse, equivalent to Matlab's nargout:

Very cool. but I'd caution against using it. I'd much rather see 
matplotlib be pythonesque than an exact duplicate of MATLAB. This is NOT 
pythonesque!

Precisely speaking, python functions ALWAYS return just one object: A 
tuple. That tuple can contain any number of other objects, and sequence 
unpacking means it can look like you're returning multiple values, but 
you're not really. i.e.

def test():
	return (1,2,3) # same as return 1,2,3

# now call it:

a,b,c = test()
(a,b,c) = test()
x = test(); a,b,c = x
x = test(); a = x[0]; b = x[1]; c = x[2]

# Are all equivalent

if one uses the last two forms, expecting() will break.

-Chris


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Christopher Barker, Ph.D.
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Chr...@no...