[Zope] Calculations within a document

[Boris Povazay]

Since I am a "Zope-Beginner" I am currently faced with some problems -
maybe you can help me with these.

Declarations & type-conversions:
How are variable-declerations done right within dtml?
Like: float x;
or: int x; float y;
y=float(x);

Calculations:
How are iterative calculations with variables done correctly in a
dtml-Method?
like: float x, 
x=0;
x=x+1

Especially the type-conversion puzzles me. I`ve read several Zope-docs,
but I have still not figured out how to do this.


Thanks a lot in advance for your reply!
-- 
Boris Povazay