Advanced Search

Question: Caching in DETools

Question:Caching in DETools

_Maxim_ 729
evalf detools
November 27 2017
0 
deq := diff(f(z), z$2)-(2*z^2+z-a-1)/z*diff(f(z), z)-((2*a+4)*z+a+1)/(2*z)*f(z):

DETools:-formal_sol(subs(a = .1, deq), f(z), order = 3)[1];
                        1+.5000000000*z+.6845238095*z^2+O(z^3)

evalf[20](DETools:-formal_sol(subs(a = .1, deq), f(z), order = 3)[1]);
                        1.+.50000000000500000000*z+.68452380953750000000*z^2+O(z^3)

The second output is padded to 20 digits, but only the first 10 digits are correct, apparently taking the cached values from the first computation. I think that's really wrong.
Please Wait...