Differential equations?



If I want to solve the ivp

y' = y(1-y), y(0)=1/2

(a logistic equation), I can use either

ic1(ode2('diff(y,x)=y*(1-y),y,x),x=0,y=1/2);

or

ic1(contrib_ode('diff(y,x)=y*(1-y),y,x),x=0,y=1/2);

both of which give me as a solution

log(y)-log(y-1) = x - log(2) - log(-1/2)

instead of

y = exp(x)/(exp(x)+1).

I can obtain this solution by some fiddling with Maxima's output, but is
there any way of obtaining the "correct" solution directly?

Thanks,
Alasdair


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