Re: [Matplotlib-users] Problems with quiver?

[Robert K. <rk...@uc...>]

Chris Neff wrote:
> I am trying out quiver using IPython (which I am new to so my apologies 
> if this is actually a IPython question) and matplotlib .80 and the 
> latest numeric. The code I try and the subsequent error:
> 
> In [1]: x=ones([5,5])
> 
> In [2]: quiver(x,x)
> ---------------------------------------------------------------------------
> exceptions.TypeError                                 Traceback (most 
> recent call last)
> 
> C:\Documents and Settings\root\Desktop\<console>
> 
> C:\Python24\Lib\site-packages\matplotlib\pylab.py in quiver(*args, **kwargs)
>    2137         hold(h)
>    2138     try:
> -> 2139         ret =  gca().quiver(*args, **kwargs)
>    2140         draw_if_interactive()
>    2141     except:
> 
> C:\Python24\Lib\site-packages\matplotlib\axes.py in quiver(self, U, V, 
> *args, **kwargs)
>     852         if do_scale:
>     853             Nmax = maximum.reduce(maximum.reduce(N))
> --> 854             U *= (S/Nmax)
>     855             V *= (S/Nmax)
>     856             N /= Nmax
> 
> TypeError: return array has incorrect type
> 
> 
> What could be the issue? Thanks for the help.

Pass in floating point arrays rather than integer arrays.

quiver, on the whole, isn't terribly robust. I've been contemplating 
writing a replacement. quiver-users: how attached are you to this API? 
Personally, it fills me with a burning rage every time I think about it.

-- 
Robert Kern
rk...@uc...

"In the fields of hell where the grass grows high
  Are the graves of dreams allowed to die."
   -- Richard Harter