#1 crash when fit power law to weird, linear function

[John Lindal]

I generated two columns of data:
0 10
1 9
2 8
. .
10 0

Then I plotted it as a vector field:
X: col 1 Y: col 2
DX: col 2 DY: col 1

When I try to fit a power law to this, I get:

Assertion failed: origMin <= origMax
code/J2DPlotWidget.cpp:1286