Hi! I'm running grass4.1 on DecStation 5000, Ultrix 4.3 with 24 meg
RAM. I have three maps, each covering a 110km x 140km area, with a
cell resolution of 10m. Each map only has one strip of 10km n/s by
the width of the map. Each strip is geographically seperate. The
three cell/ files are 1, 1.4 and 1.8 megs. When I use d.rast to
display these maps seperately, or overtop of each other (the -o
option) everything displays fine in a few seconds; HOWEVER, after
running r.patch to stick the three maps together, the resulting map
(about 4.2 megs) takes about 45 MINUTES to d.rast!!!Anybody have any idea what's up? Did I just overshoot memory
requirements or something? The disk drive does not seem to pounding
away like it's swapping like crazy. I've even shutdown the system
and powered back up, but same results.
Professor Steven Rose, R.P.F. Phone: (705) 324-9144
Sir Sandford Fleming College FAX: (705) 878-9312
PO Box 8000, Lindsay, Internet: srose@flemingc.on.ca
Ontario, CANADA K9V 5E6
I believe someone on the list had this same problem recently.
I think the problem is due to the color table created by
r.patch which is very large because it is attempting to preserve
all the colors, if you do not need to keep the original colors
try running d.colors on the new image
cheers Tom
Tom Charnock O--O
Dept Civil Engineering (~~~~)
Aston University ( __ )
Birmingham B4 7ET UK /|\ /|\
charnotw@sun.aston.ac.uk