Hi Ming,
You have to give the Z-axis name along with the
"set axis/DEPTH" command. Proceed as follows :
1. Open your dataset ( yes? use mydataset.nc )
2. Get the variable name ( Yes? show data )
let us say it is "myvar"
3. Get the Z-axis name ( yes? show grid myvar )
You will get four names in the first column, and the
Z-axis will be the third one.
let it be "ZAXIS"
4. Assign "positive up" attribute using "set axis" command
yes? set axis/DEPTH ZAXIS
5. Now the "show grid" command should show a "-" sign in the
third column for the Z-axis (third line) like :
ZAXIS DEPTH (m) 20 i- 0 5000
6. Make the plot.
If these steps does not fix your problme, please send me the
output of "show data" and "show grid" command to me.
There are other means to fix your problem. See the discussions
starting with this one in the Ferret mail archive :
http://ferret.pmel.noaa.gov/Ferret/Mail_Archives/fu_2003/msg00548.html
Regards,
Jaison
On Mon, 19 Jun 2006, Ming Yang wrote:
Hi, guys
I have a question for you. I have a 4D dataset rho (3D in space and 1D in
time), which is the density of the seawater in the ocean. I want to plot
the vertical profile of rho at a specific point (say I=9, J=67) and at a
specific time (L=1). The problem is how can I make the y axis plotted as
downward positive? I tried to use "SET AXIS/DEPTH", but I always get the
error message, "**ERROR: invalid command: unknown axis:". Does anybody know
why? Thank you for your attention.
Best,
Ming