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[python #TKX-201706]: tinkering with coloured hodograph

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  • Subject: [python #TKX-201706]: tinkering with coloured hodograph
  • Date: Tue, 27 Feb 2018 13:24:25 -0700
HP,

If you want to use a colormap and a norm with plot_colormapped, you need to 
pass them in as the "norm" and "cmap" keyword arguments, respectively:

h = Hodograph(ax, component_range=60)
h.add_grid(increment=10)
norm, cmap=ctables.registry.get_with_range('test',0,60)
h.plot_colormapped(u,v,np.hypot(u,v), norm=norm, cmap=cmap)

I have opened an issue reminding us to add something like this to the examples:

https://github.com/Unidata/MetPy/issues/752

Thanks for the report!

Ryan

> ---------- Forwarded message ----------
> From: HansPeter Roesli <address@hidden>
> Date: Tue, Feb 27, 2018 at 6:05 AM
> Subject: tinkering with coloured hodograph
> To: address@hidden
> 
> 
> Hi -
> 
> I would like to draw a hodograph with more contrast than given by the
> default colours. So, I am going like
> 
> h = Hodograph(ax, component_range=60)
> h.add_grid(increment=10)
> norm,cmap=ctables.registry.get_with_range('test',0,60)
> h.plot_colormapped(u,v,np.hypot(u,v),bounds=norm,colors=cmap)
> 
> While plot_colormapped without bounds and colors works as expected, the
> above code ends in an error message
> 
> ...
> File 
> "C:\Users\hproe_000\AppData\Roaming\Python\Python36\site-packages\matplotlib\colors.py",
> line 793, in __init__
> N = len(colors)
> 
> TypeError: object of type 'ListedColormap' has no len()
> 
> Any idea what I am doing wrong here?
> 
> cheers, HP
> 

Ticket Details
===================
Ticket ID: TKX-201706
Department: Support Python
Priority: Low
Status: Closed
===================
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