Jeff .... sorry to hear that you have given up on the 'calculator'
for genotype coefficient calculations and have gone back to editing
the cultivar file. In principle, the calculator does nothing more
than edit the cultivar file for you, run the model, compare the
outputs with actual data and go round again in accordance with rules
that you, the operator can set. (Remember, the rules sets provided in
DSSAT are given as guides ... they can be changed by an operator,
broken down to deal with individual coefficients, or sequenced in a
different way than originally presented). The caclulator (and this
would be the same for any similar software) is there to speed up the
process that you can go through, of course, by editing the cultivar
file, and it has proved to be quite useful not only when data from a
number of locations need to be analysed, but also to 'control' a
number of iterations at one location when looking at one coefficient.
If you have the time to do everything manually, fine .... but most of
us need a little help and many have found that the calculator is
useful in providing this 'little help'.     Regards .... Tony