d.rast VERRRRY SLOWWWW ????

[charnotw]

> 
> 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 at 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 at sun.aston.ac.uk