Following an earlier thread (Collect-And-Sqrt) where a solution using applyrule was proposed (and that solution works), I tried to use applyrule to implement some of the trig half-angle relationships. Immediately I ran into trouble:

Say I want to use the rule

r:=cos(th::algebraic)=2*cos(th/2)^2-1;

so I say

applyrule(r,cos(alpha));

and Maple promptly goes into an...

Hi, this  must have been asked numerous time, but I cannot find it in MaplePrimes:

How does one "collect" sqrt terms? collect(expression,sqrt) does not work because sqrt is actually represented as ^(1/2) in  Maple. collect on '^' does not work either... ??

Mac Dude

I have a procedure which accepts arguments of a (created by myself) type which are records, like so:

Subs:=proc(eqn::seq(equation),elemt::Element,$);
...

Here "Element" is  type I have defined; it is a record with certain fields present.

My question: will this work with option remember? I have the procedure sort-of working without the remember option, but I need to make it work recursively (the Element record can have fields which contain names of other records of type Element...

I have written a procedure to overload a new "Subs" function. It uses a seq of equations as its first argument followed by the object to act upon (yes, it is to have subs functionality on these objects). I find the overloading works when I have just one equation in the argument list, but with more than one it never calls any of the procedures. The code worked with multiple equations before I overloaded it (i.e. the first proc was verified by itself). FWIW the objects (elemt or bm...

Hi; I am working on a package where the data mostly come in Maple records with a varisble number of fields with different names. At least one field in each record has a 6 by 6 matrix, the expressions of which involve the values associated with at least some of the other fields.

Occasionally I have the need to, say, apply a function to each of these fields. E.g., I want to substitute a value for a specific name; this name may show up in several fields and also will show up in the matrix.