[Scipy-tickets] [SciPy] #1605: Bug in scipy.interpolate.griddata (numerical problem)
SciPy Trac
scipy-tickets@scipy....
Wed Feb 22 14:31:10 CST 2012
#1605: Bug in scipy.interpolate.griddata (numerical problem)
----------------------------------------+-----------------------------------
Reporter: schicketanz | Owner: somebody
Type: defect | Status: new
Priority: high | Milestone: Unscheduled
Component: scipy.interpolate | Version: 0.10.0
Keywords: griddata numerical problem |
----------------------------------------+-----------------------------------
Changes (by pv):
* priority: normal => high
Comment:
This indeed seems to be a precision error -- for this input data, the
triangulation qhull produces contains nearly (but not completely)
degenerate triangles, for which the computed barycentric transforms are
nearly singular. This then confuses
`scipy.spatial.qhull._find_simplex_directed` to thinking that certain
points lie outside the convex hull, although in reality they don't.
This doesn't seem to occur on all machines, probably depends on compiler
etc.
The solution is to check the validity of the transform, and discard the
simplices which appear to be degenerate. Here's a fix:
- https://github.com/pv/scipy-work/commits/bug/1605-griddata-baryfix
--
Ticket URL: <http://projects.scipy.org/scipy/ticket/1605#comment:2>
SciPy <http://www.scipy.org>
SciPy is open-source software for mathematics, science, and engineering.
More information about the Scipy-tickets
mailing list