Is it possible to detect the highest order (or generally all orders) of derivatives in an expression?
eqn = D[a[x,t],t] == D[a[x,t],x,x]
How would I go about detecting that the highest order of the partial derivative in x is 2 in eqn?
I was thinking of using MatchQ, however this
MatchQ[Derivative[2, 0][a][x, t], eqn]
just returns False.