MODAPS PCR 10-001

PCR Number 10-001
Date 2010-02-04
Initiator James Kuyper
Abstract Mandriva-2008 certification for Level 1B PGEs.
Problem Statement It was not known whether the Level 1 PGEs would produce output files on Mandriva Linux minions that contained unacceptable differences from those produced on IRIX or Mandrake Linux Machines.
Description of Change Ideally, none should be needed.
Products Affected M[O|Y]D01, M[O|Y]D03, M[O|Y]D021KM, M[O|Y]D021QA, M[O|Y]D02HKM, M[O|Y]D02OBC, M[O|Y]D02QKM
Software Affected PGE01, PGE02
Processing String to Receive the Change Terra Forward, Terra Reprocessing, Aqua Forward, Aqua Reprocessing
Downstream Product Effects All MODIS PGEs are downstream of the Level 1 PGEs.

Small differences in all floating point values in the Level 1 products are to be expected, as they were between IRIX and Mandrake Linux products. These will lead to small numbers of minimum differences in discrete quantities, too. In rare instances, these small differences may lead to much larger ones, such as when a small difference in the radiance value crosses the threshold for marking the pixel as saturated.

All of these effects will propagate to downstream products; so exactly equivalent product files should not be expected.
Data Granules to be Used for Science Testing PGE01: 2008-284 - 2008-286
PGE02: 2008-286 12:10 - 13:50
Justification MODAPS is switching over from Mandrake to Mandriva, and we need to be sure that the differences won't cause unacceptable changes to the product files.
Effective Date for Implementation of Change  
Status Science test run at MODAPS, evaluated by James Kuyper and LDOPE.