Hi Jim...
Sorry, I missed typed last night. You should use parentheses for the range
values. The square brackets are used for options [units, miss, etc]. See
section IIIb of the README.text file.
Please let me know if you have any more problems with this. (Especially since
I always use comma-separated values... ;-)
tom
Jim Cookas wrote:
tom, all
thanks a ton for the suggestion...it looks like this will be the method of
choice for speeding up image display...i implemented the changes today, but i'm
having a problem getting the image to display...i think it is a problem with my
ascii file format...
i am using tab-spaced values...here is what test.tsv looks like:
(Down_Range,Cross_Range)->(RCS)
Down_Range[-755.383:755.383] Cross_Range[-755.383:755.383] RCS
[ 256 RCS values for Down_Range #0 ]
[ 256 RCS values for Down_Range #1 ]
.
.
.
[ 256 RCS values for Down_Range #255 ]
when i try to load this file into visad, i get these messages at the terminal:
Unit name problem:visad.data.units.ParseException: negative sign follows
decimal point with -755.383:755.383
Unit name problem:visad.data.units.ParseException: negative sign follows
decimal point with -755.383:755.383
any ideas on the problem?...thanks again!!
jc
-----Original Message-----
From: Tom Whittaker [mailto:tomw@xxxxxxxxxxxxx]
Sent: Monday, January 05, 2004 9:43 PM
To: Jim Cookas
Cc: Jim Koutsovasilis; visad@xxxxxxxxxxxxxxxx
Subject: Re: slow 2d image generation
Jim:
I believe that part of the slowness in "reading" is that the form of
your data is producing an IrregularSet, which VisAD needs to
"triagulate" when it does the display. If your data points are a
"regular grid" (meaning, regular/constant spacing between
data points)
you can use the format:
Down_Range[-755.383:-200], Cross_Range[-755.838:-500], RCS
(where the '-200' and '-500' should be the actual ending
values for the
sample domain. If you do this, and then put all the RCS
values (along
the Cross_Range)for a single Down_Range on one input line. The text
reader will compute the actual domain sampling coordinate for
each "RCS"
value. When you do this, the TextAdapter will make a
Gridded2DSet for
the sampling domain, and it is handled faster than the IrregularSet.
Of course, there will be some overhead for reading and
decoding the text
in either case, so I agree with JimK -- you may want to
create your own
reader.
tom
--
Tom Whittaker (tomw@xxxxxxxxxxxxx)
University of Wisconsin-Madison
Space Science and Engineering Center
Cooperative Institute for Meteorological Satellite Studies
Phone/VoiceMail: 608.262.2759
