Subject: Numerical Error Caused by Negative CRs
Name: R. Havis
Date: January 19, 2011
Variants affected: ALL

Description: When the FFE changes the crown ratio (CR) of of a tree, it
             sets the crown ratio carried in the base model to a negative value.
             When all trees in a stand were killed in a simulated fire (so total
             probability in the treelist equals zero) the crown routines did not
             set the crown ratios back to positive values. This caused a numerical error.
             It has been corrected.

Impact on users: When all trees in a stand are killed by fire, FVS will process the stand
                 through until the end of the simulation rather than potentially failing
                 with a numerical error.

Files:

CROWN - added logic to set CR to absolute value of CR when branching out of routine
        with trees in tree list but total probability = 0.

./ak/src/crown.f
./an/src/crown.f
./base/src/revise.f
./bm/src/crown.f
./ca/src/crown.f
./ci/src/crown.f
./cr/src/crown.f
./cs/src/crown.f
./cs_new/src/crown.f
./ec/src/crown.f
./em/src/crown.f
./ie/src/crown.f
./ls/src/crown.f
./ls_new/src/crown.f
./metric/strp/src/estab.f - synchronized with standard version
./nc/src/crown.f
./ne/src/crown.f
./ne_new/src/crown.f
./ni/src/crown.f
./ni/src/cwcalc.f - reved back to previous version by removing absolute value in CL calculation
./pn/src/crown.f
./sn/src/crown.f
./so/src/crown.f
./tt/src/crown.f
./ut/src/crown.f
./wc/src/crown.f
./ws/src/crown.f
