TABEX is a look up and interpolation function.  In this case you define CO2
as input, the model will search CO2X and find the equivalent CO2Y value to
calculate PCO2 as output.  10 means that there are 10 (x,y) pairs.
 
TABEX is defined as a separate subroutine in CERES.  It is very commonly
used as a way to extract data from response functions for all the DSSAT crop
models.
 
I hope that this helps.
 
Regards,
 
Gerrit
 
 
At 02:17 PM 5/8/97 +0200, Andre du Toit wrote:
>In CERES3 the following source code is used to simulate the influence
>of C02 on dry matter production
>
>
>      DATA CO2X /   0, 220, 330, 440, 550, 660, 770, 880, 990,9999/
>      DATA CO2Y /0.00,0.81,1.00,1.03,1.06,1.10,1.13,1.16,1.18,1.25/
>
>      PCO2  = TABEX(CO2Y,CO2X,CO2,10)
>      PCARB = PCARB*PCO2
>
>Could someone please explain to me how this is calculated and what
>TABEX mean.
>
>Regards Andre
>
 
 =======================================================================
Gerrit Hoogenboom
Associate Professor
Department of Biological and Agricultural Engineering
The University of Georgia
Griffin, Georgia 30223-1797, USA
 
Phone:  770-229-3438 (New !)
FAX:    770-228-7218
E-mail:  [log in to unmask]
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