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In the last figure 4 of contour_demo.py, the positioning of the
vertical colorbar looks too low.  I would expect it to align roughly
with the vertical extent of the image axes.  Is this intentional,
configurable, or a bug?

Also, in many of the contour examples, the text labels overlap the
contour lines, especially when the text labels are large.  Should we
revisit the code which removes line segments that overlap the text
code to see if we can improve this a bit?

JFH

Jordan, Gary,

I have been working on another implementation of quiver functionality.  It is not ready to commit yet, but I think I have the transforms worked out reasonably well.  The arrows never get distorted, and their orientation is preserved as the axes are manipulated.  Length can be preserved or not, depending on the units one chooses. Below a threshold, the whole arrow is scaled down as its length is reduced; above that threshold, only the length changes. I am subclassing PolyCollection, so there is full flexibility in rendering with or without an edge.

I expect I will be ready to commit something within a week.

Eric

Eric Firing wrote:
> Jeff,
>
> Thanks for the report.  I have committed a bugfix combined with a speedup: the check for gray will not occur if the image is cached.
>
> Eric
>
>   

Thanks Eric - that works fine.

-Jeff

-- 
Jeffrey S. Whitaker         Phone : (303)497-6313
NOAA/OAR/CDC  R/PSD1        FAX   : (303)497-6449
325 Broadway                Boulder, CO, USA 80305-3328

Jeff,

Thanks for the report.  I have committed a bugfix combined with a speedup: the check for gray will not occur if the image is cached.

Eric

----- Original Message -----
From: Jeff Whitaker <js...@fa...>
Date: Friday, June 2, 2006 1:07 pm
Subject: [matplotlib-devel] RGBA in imshow
To: matplotlib development list <mat...@li...>

> Hi all:
> 
> It looks like one can no longer plot an array of RGBA values in 
> imshow - 
> I suspect this is a consequence of the recent changes to the way 
> colors 
> are handled.  For example
> 
> from pylab import *
> # make a random rgba matrix
> rgba = ones((64,64,4),'f')
> for k in range(3):
>   rgba[:,:,k] = rand(64,64).astype('f')
> imshow(rgba)
> show()
> 
> works in 0.87.2, but fails with
> 
> Traceback (most recent call last):
>  File "/Users/jsw/lib/python/matplotlib/backends/backend_gtk.py", 
> line 
> 283, in expose_event
>    self._render_figure(self._pixmap, w, h)
>  File 
> "/Users/jsw/lib/python/matplotlib/backends/backend_gtkagg.py", 
> line 72, in _render_figure
>    FigureCanvasAgg.draw(self)
>  File "/Users/jsw/lib/python/matplotlib/backends/backend_agg.py", 
> line 
> 389, in draw
>    self.figure.draw(renderer)
>  File "/Users/jsw/lib/python/matplotlib/figure.py", line 531, in draw
>    for a in self.axes: a.draw(renderer)
>  File "/Users/jsw/lib/python/matplotlib/axes.py", line 991, in draw
>    im.draw(renderer)
>  File "/Users/jsw/lib/python/matplotlib/image.py", line 184, in draw
>    im = self.make_image()
>  File "/Users/jsw/lib/python/matplotlib/image.py", line 130, in 
> make_image    im.is_grayscale = (self.cmap.is_gray() and
>  File "/Users/jsw/lib/python/matplotlib/colors.py", line 634, in 
> is_gray    return (alltrue(self._lut[:,0] == self._lut[:,1])
> 
> with the latest svn.
> 
> This patch to image.py seems to fix it, but I'm not sure it's the 
> right 
> solution
> 
> --- /Users/jsw/lib/python/matplotlib/image.py.orig      2006-06-02 
> 17:04:52.000000000 -0600
> +++ /Users/jsw/lib/python/matplotlib/image.py   2006-06-02 
> 17:05:24.000000000 -0600
> @@ -127,8 +127,10 @@
>             im.flipud_in()
> 
>         im.set_bg( *bg)
> -        im.is_grayscale = (self.cmap.is_gray() and
> -                           len(self._A.shape) == 2)
> +        if len(self._A.shape) == 2:
> +            im.is_grayscale = self.cmap.is_gray()
> +        else:
> +            im.is_grayscale = False
> 
>         im.set_interpolation(self._interpd[self._interpolation])
> 
> 
> -Jeff
> 
> 
> -- 
> Jeffrey S. Whitaker         Phone  : (303)497-6313
> Meteorologist               FAX    : (303)497-6449
> NOAA/OAR/PSD  R/PSD1        Email  : Jef...@no...
> 325 Broadway                Office : Skaggs Research Cntr 1D-124
> Boulder, CO, USA 80303-3328 Web    : http://tinyurl.com/5telg
> 
> 
> 
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