MATLAB: Does the code that worked in R2009a fail in R2009b in Symbolic Toolbox 5.3 (R2009b)

fevalinconsistentsolvesymbolicSymbolic Math Toolbox

A symbolic FEVAL statement that worked in R2009a does not work in R2009b. The following statement does not get evaluated:
   myexp = 't/100 + sum((7*r8*exp(r8*t) - exp(r8*t) + 6*r8^2*exp(r8*t))/(9*r8^2 + 10*r8 + 2), r8 in RootOf(s8^3 + (5*s8^2)/3 + (2*s8)/3 + 1/3, s8))/100 - 1/50'
TD_sol2 = feval(symengine,'RootOf::exact',myexp)

Best Answer

In R2009b, the maximum substitution depth changed from 100 to 1. This is why the line does not evaluate completely. To return to the behavior of R2009a, you may add the following command before the FEVAL statement is called:
evalin(symengine,'LEVEL:=100:')
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