Thanks to some debugging from Ghansham Sangar (SAC/ISRO) and plots
from Chris Pudney, this indeed looks like a precision problem manifested
in the surface normal generation. The double-precision Set classes won't
help with this. To help verifiy this is the case, you might try
scaling up the spatial dimensions of your data while we consider some
On 5/22/12 9:27 PM, Pudney Chris (ext) GBJH wrote:
Here's another example of the issue Tomas is talking about (from the
The artefacts appear when the sampling resolution along the m/z axis
is high (attachment 1).
They're not present at lower resolutions (attachment 2).
Floating point precision could well be the issue.
On 22/05/12 08:11, Tomas Pluskal wrote:
Thank you for the tip.
I would like to try that, but what class should I use instead of the
There seems to be only Gridded2DDoubleSet, but no equivalent for the
By the way, please check the other batch of screenshots I sent:
There the same issue appears although the spacing between the data
points is not so close (around 1).
On May 21, 2012, at 10:41 PM, Tom Rink wrote:
With the Linear2DSet you've defined, the points are pretty close, maybe
too close for single precision. You could try the double-precision
of the Set classes.
G0 Cell Unit, Okinawa Institute of Science and Technology Graduate
1919-1 Tancha, Onna-son, Okinawa 904-0495, Japan
This message may contain confidential information. If you are not the
designated recipient, please notify the sender immediately, and delete
the original and any copies. Any use of the message by you is prohibited.
visad mailing list
For list information, to unsubscribe, visit: