Yeah of course! Thats embarrassing :D. Thanks for your help anyway!

Yeah of course! Thats embarrassing :D. Thanks for your help anyway!

Well i had a look at ?indexed and (believe to have) learned that indexing a variable(=name) creates a table which means that roughly speaking you have several variables(=names), differing just in the index, which are contained in one table (the name of the table is probably the non indexed name).

As far as i understood one is free to use those variables (almost) like normal variables ("An indexed name may appear almost anywhere a name can appear"). I just have to figure out what almost means i guess and in which cases i can't or shouldn't use indexed names.

Hm thinking about it the conclusion could be that with the introduction of t_a and t_b i made a table which is called t and therefore Maple had problems using t as an integration variable. Am i correct?

Well i had a look at ?indexed and (believe to have) learned that indexing a variable(=name) creates a table which means that roughly speaking you have several variables(=names), differing just in the index, which are contained in one table (the name of the table is probably the non indexed name).

As far as i understood one is free to use those variables (almost) like normal variables ("An indexed name may appear almost anywhere a name can appear"). I just have to figure out what almost means i guess and in which cases i can't or shouldn't use indexed names.

Hm thinking about it the conclusion could be that with the introduction of t_a and t_b i made a table which is called t and therefore Maple had problems using t as an integration variable. Am i correct?

Thanks for the fast response. It works fine now. But what is the difference now?

And more important: Could i encounter similar problems (maple wont calculate a result) when differentiate or manipulate expressions with indexed variables which would be fine when not being indexed?

Thanks for the fast response. It works fine now. But what is the difference now?

And more important: Could i encounter similar problems (maple wont calculate a result) when differentiate or manipulate expressions with indexed variables which would be fine when not being indexed?