Franz Lehner wrote:
>
> I have been playing with CCR (asked recently here by a physicist).
> It is a hypergroup like object and I tried the following:
> Define multiplication from the basis into FreeModule(basis)
> and then extend it linearly.
> However I keep getting the following error when compiling the attached file
> (a simplified version). What is expected to be an ordered set here?
> ------------------------------------------------------------------------
> initializing NRLIB CCRA for CCRAlgebra
> compiling into NRLIB CCRA
> compiling exported * : ($,$) -> $
> ****** comp fails at level 1 with expression: ******
> error in function *
>
> ($)
> ****** level 1 ******
> $x:= $
> $m:= (OrderedSet)
> $f:=
> ((((|res1| #) (|y1| # #) (|x1| # #) (|last| #) ...)))
>
> >> Apparent user error:
> Cannot coerce $
> of mode (Algebra R)
> to mode (OrderedSet)
>
> )abbrev category HGB HGBasis
> ++ blabla
> HGBasis(R:CommutativeRing):Category == OrderedSet with
> _*:(%,%)-> FreeModule(R,%)
>
> )abbrev domain CCRB CCRBasis
> ++ blabla
> CCRBasis(R:CommutativeRing):HGBasis(R) == Symbol add
> (x:%,y:%):FreeModule(R,%) == monomial(1,x)
>
> )abbrev domain CCRA CCRAlgebra
> ++ blabla
> CCRAlgebra(R:CommutativeRing):Algebra(R) == FreeModule(R,CCRBasis(R)) add
> Rep:= FreeModule(R,CCRBasis(R))
> x,y:%
> x1,y1:Record(k:CCRBasis(R),c:R)
>
> x * y ==
res : % := 0
> for x1 in listOfTerms (x::Rep) repeat
> for y1 in listOfTerms (y::Rep) repeat
> res1:% := (x1 k * y1 k)
> res:= (x1 c * y1 c)*res1 + res
> res
>
This example (after adding missing initialization of 'res') works
now. The problem was caused by compilation of types of imported
functions. Compiler got confused because in such types '$'
means domain in which function was defined while compiler
treats '$' as current domain. In revision 1138 I commited
a workaround which does not handle some complicated cases, but
should handle the most important ones (and can be extended
if needed).
--
Waldek Hebisch
[email protected]
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