plotting windchill with grads

[Frank Bandle]

Hi

i try to make a windchill-chart. But it´s hard :-)
I have all needed parameters defined here in my script, but i got  
errors by doing things with the
grads math functions.


-----  snip
'define t3=TMP2m-273.16'
'define u10=UGRD10m'
'define v10=VGRD10m'

* // Windspeed in km/h  = (m/s) *3.6
* // try with math_pow
* // wis = Windspeed in km/h (10m)
* // t2 = 13.12 + 0.6215 * T(2m) - 11.37* (wis)pot(0.16) + 0.3965 * T 
(2m)* (wis)pot(0.16)
*
'define wis = (mag(u10,v10)*3.6'
rc = math_pow(wis,0.16)

t2=13.12 + 0.6215*t3 - 11-37*rc + 0.3965*t3*rc

'set gxout contour'
'd t2'
....
---  snip -----------


Error comes up doing math_pow with a data field - here with "wis".
If i use a fixed value instead of "wis" - math_pow is working, but  
this is not helping.

Anybody, any ideas.
It looks simple, but i cannot see the solution at the moment.

Regards and thank you

Frank



Dipl. Met. Frank Bandle
frank at bandle.com * FeMax Wetteragentur IT & Medienberatung
www.wetter365.net * www.femax.de
ICQ/AIM: f2topcat *Skype: fraban
GnuPG/PGP Key-ID: 0x8B8BCC29


-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://gradsusr.org/pipermail/gradsusr/attachments/20070126/15738760/attachment.html