Subject: Why cannot Maxima calculate some simple sums
From: Leo Butler
Date: Sat, 5 Jun 2010 17:30:38 +0100 (BST)
On Sat, 5 Jun 2010, John Lapeyre wrote:
< maxima's behavior is a little puzzling with sums.
<
< (%i2) integrate(1/n^2,n,1,inf);
< (%o2) 1
<
< (%i3) sum(1/n^2,n,1,inf);
< (%o3) 'sum(1/n^2,n,1,inf)
< ? search the manual
<
< (%i4) sum(1/n^2,n,1,inf),simpsum; /* why not simpintegrate ? */
< (%o4) %pi^2/6
<
< (%i5) sum(1/n!,n,0,inf),simpsum;
< (%o5) 'sum(1/n!,n,0,inf)
<
< (Now the user assumes that maxima can't do this sum because the manual is clear about
< simpsum and seems to imply that this is all there is to simplifying sums)
<
< Maybe no one got around to fixing this inconsistency... or maybe its hard to
< change without breaking something.
I guess there are two responses. First, the Maxima online help system
needs to be improved. In comparison to Octave's, for example, it lacks
cross-referencing. However, and second, users often forget that
?? sum
will list all topics which contain the 3 characters s u m.
In particular, you will find 'simplify_sum'.
I can't answer your question about the difference between simplification
flags for sum and integrate.
Leo
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