iraf.net

NUMBER: 559
MODULE: longslit.transform
SYSTEM: -V2.12.3
DATE: Tue Aug 7 10:39:13 MST 2007
FROM: valdes

BUG: When using log resampling (xlog=yes or ylog=yes) it is possible to get a segmentation error. This is caused by taking the log and anti-log of coordinates and not getting back exactly the same value due to real precision problems. This process caused an attempt to go outside the valid range of the interpolator. This may be a rare problem but if it does happen one may be able to use the x1, x2, y1, y2 values to work around the problem. The workaround for a future release is to use double precision and to impose range limits on data passed to the interpolator.

STATUS: Fixed for the next release.