I have been struggling with trying to make a slice plot of some FLASH data that is an odd size; the volume is 1 kpc square in x and y, and 40 kpc tall in z.  The grid sizes vary widely, as expected. I have two questions: one, I would like to understand the odd behavior that I get with regular SlicePLots, and I would like some help using the FixedResolutionBuffer, which I *suspect* is the way I want to go, but I have not been able to make it work.  I am using the newest version of yt (upgraded this morning!) on Mac OS 10.7.5.

The SlicePlot weirdnesses:
from yt.mods import *
%matplotlib inline
import matplotlib.pyplot as plt
import matplotlib.image as mpimg
import matplotlib.colorbar as cb
import numpy as np
#First try a 20 kpc tall box
slc = SlicePlot(pf, 'x', 'Density',center='c',width=((1,"kpc"),(20.0,"kpc")))
slc.annotate_title('This is a Density plot')
slc.save('test_20kpc.png')
slc.show()

#Now try a 5 kpc tall plot
slc = SlicePlot(pf, 'x', 'Density',center='c',width=((1,"kpc"),(5.0,"kpc")))
slc.annotate_title('This is a Density plot')
slc.save('test_5kpc.png')
slc.show()

#Please see plot at http://i.imgur.com/L1YORNK.png ; note that it seems to filling
#a different part of the plotting "window"

#Now try a 2 kpc tall plot
slc = SlicePlot(pf, 'x', 'Density',center='c',width=((1,"kpc"),(2.0,"kpc")))
slc.annotate_title('This is a Density plot')
slc.save('test_2kpc.png')
slc.show()

#Please see plot at http://i.imgur.com/Bq1WaIP.png ; note that it seems to filling
#even MORE of the plotting "window", but that the density labels were cut off a bit.

OK, now the part that doesn't work.  After reading, I decided that an frb must be
the way to go, so I tried
frb = FixedResolutionBuffer(slc, (0.0, 1.0, 0.0, 1.0), (1024,1024))
plt.imshow(frb['Density'])
plt.savefig('test_figure.png')

and I get the following error.  Note: I also tried slc.to_frb and that didn't work either.
```---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
<ipython-input-17-e68719d58ae4> in <module>()
----> 1 frb = FixedResolutionBuffer(slc, (0.0, 1.0, 0.0, 1.0), (1024,1024))
2 plt.imshow(frb['Density'])
3 plt.savefig('test_figure.png')
4
5

/Users/kde/yt-x86_64/src/yt-hg/yt/visualization/fixed_resolution.pyc in __init__(self, data_source, bounds, buff_size, antialias, periodic)
89         self.antialias = antialias
90         self.data = {}
---> 91         self.axis = data_source.axis
92         self.periodic = periodic
93

AttributeError: 'SlicePlot' object has no attribute 'axis'

```
THanks in advance for any help.
cheers
kathy

--
Kathy DeGioia Eastwood, Ph.D.
Professor of Physics and Astronomy
Northern Arizona University
Flagstaff, AZ 86011-6010
Ph: 928-523-7159   FX: 928-523-1371
Kathy.Eastwood@nau.edu
deliveries: 602 S. Humphreys St., Bldg 19 Rm 209