Question: (Apparent) Problem between seq/sum and alias


My name is Francisco Navarro. I have a problem when using diff and alias, together with seq or sum.

A very simplified worksheet of what I mean would be


alias(a1 = a1(r), a2 = a2(r), a3 = a3(r))

array1 := [a1, a2, a3]

array2 := [seq(cat(a, i), i = 1 .. 3)]

array1 - array2

This gives [0,0,0] so they are the same thing but, under differentiation, they do not behave the same way (so they are NOT exactly the same object for Maple)

diff(array1, r)

diff(array2, r)

which are different. Any idea of what is wrong with this?

I need to create long arrays with funcions that depend on several values and then differentiate those arrays. But clearly this approach does not work. Thank you for your answer.


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