On Fri, Apr 16, 2010 at 2:22 PM, Alec Mihailovs <[email protected]> wrote: > On Apr 16, 1:50 pm, Alec Mihailovs <[email protected]> wrote: >> >> Or even more simple -if A is the matrix consisting of all non-erased >> columns, use A.transpose()*(A*A.transpose()).inverse() for decoding,
Do you mean A is the matrix of all n^k codewords, but you remove the columns corresponding to the erasure positions? I don't know what you mean by A. >> applying it to the non-erased part. > > And if A*A.transpose() is singular, the same thing, probably, could be > done with the matrix, obtained from A by removing a column, but I'm > not sure - there may be, perhaps, cases, when removing more than 1 > column is necessary - that would make the procedure more complicated > (in the worst cases.) > > Alec > > -- > To post to this group, send email to [email protected] > To unsubscribe from this group, send email to > [email protected] > For more options, visit this group at > http://groups.google.com/group/sage-support > URL: http://www.sagemath.org > -- To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
