how to get S-N, E-W in a plot

["Yogesh K. Tiwari" <ktiwari@xxxxxxxxxxxxxxx>]

Hello,

I have very simple question.

I run the following script and the generated plot 
shows the lat and lon values on the axises like 
-50,.. ,+80 etc and -180,.., -40 etc.

BUT I need the axix north south and west east 
notation like 50S,.. 80N and 180W, 40W etc.

Kindly suggest me in  this script what to do to 
get my desire axis form.

!+++++++SCRIPT++++++++++++++++++

set window/aspect=0.7

plot/vs/col=2/nolab/vlimits=0:80 \
/hlimits=-180:-40  lon[l=1:1000],lat[l=1:1000]

ppl dfltfnt,@tr

ppl axlsze 0.26 0.26

go margins  " "  " "   2.2 " "

ppl yaxis 0,80,15

ppl xaxis -180,-40,15

ppl plot

go land

frame/file=plot.gif

!+++++++++++++++++++++++++++++++++++

Thanks for your help,

Regards,
Yogesh
--

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Yogesh Tiwari,
Max-Planck Institute for Biogeochemistry,
Hans-Knoell Strasse 10,
D-07745 Jena,
Germany

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