I don't see what is wrong in your example. If you want vectors in RR^2, replace ZZ^2 with RR^2 in the input line.
John On 5 June 2012 09:01, Jan Pöschko <[email protected]> wrote: > Hi everyone, > > I am working on the Summer of Code Lattices project and ran into a problem > when trying to subclass Lattice from FreeModule_submodule_with_basis_pid. If > I'm getting it right, the coefficient ring R is to be specified as parameter > ambient (in the form R^n), followed by the basis vectors in K^n. Now I don't > understand why the basis is coerced to the fraction field of R (if not R > itself), e.g. > > sage: from sage.modules.free_module import > FreeModule_submodule_with_basis_pid as FMs > sage: FMs(ZZ^2, [(0.5,0.25), (1.0,0)]) > Free module of degree 2 and rank 2 over Integer Ring > User basis matrix: > [1/2 1/4] > [ 1 0] > > I would like to allow creating lattices of points in RR^n (the real vector > space) with integer coefficients (ZZ), which is probably the most common > form of point lattices. As lattices really are free modules, it would be > good to inherit from them, but with the basis being kept in RR^n if given > therein. > > I tried a workaround by disabling checking and echelonization of the basis > (see the details of my approach), but this doesn't work actually. > > Is there a reason why FreeModule is restricted in this way? Should it be > patched? Or should lattices subclass from something else? > > Thanks, > Jan > > -- > To post to this group, send an email to [email protected] > To unsubscribe from this group, send an email to > [email protected] > For more options, visit this group at > http://groups.google.com/group/sage-devel > URL: http://www.sagemath.org -- To post to this group, send an email to [email protected] To unsubscribe from this group, send an email to [email protected] For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
