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**935**- (**download**) (**annotate**)*Tue Sep 20 10:14:57 2005 UTC*(14 years ago) by*maechler*File size: 2802 byte(s)

update TODOs

- Sparse matrix methods can now be based on the CHOLMOD package. We will need to migrate from the current code to CHOLMOD-based code using #ifdef USE_CHOLMOD. Some of the things to be done - Move documentation from subdirectories of src to inst/doc - Write utilities to create a cholmod_sparse pointer from a dgCMatrix or lgCMatrix (or zgCMatrix) object without copying and allocating. - Start adding simple S4 methods (rcond, %*%, +, cbind, t). - Report the problem in the Linux ldexp manual page. The second and third calls in the Synopsis should be to ldexpf and ldexpl. - [,] indexing: for sparse "works", but not yet for negative indices! - group generics: "Arith" (partly done), but also "Compare", "Math" etc; see ?Math and the examples in ?SetGeneric - methods for rbind and cbind where they make sense (Kurt is particularly interested in dgCMatrix ones, for pkg 'arules') ****> UNFEASIBLE as long cbind is function(..., *) !!!! <******* --> follow John's proposition cbind(x, ...) via Generic cbind2(x,y)? - consider moving alloc3Darray from ./src/Mutils.c to $(RSRC)/src/base/array.c - slot "factors" maybe should move up to "Matrix" ------- - provide methods for "dspMatrix" and "dppMatrix"! - implement (more) methods for supporting "packed" (symmetric / triangular) matrices; particularly something like pack() and unpack() [to/from our classes from/to "numeric"] --- have already man/unpack.Rd but no method yet! (have some dtr* <-> dtp*) - implement diagonal Matrix class "ddiMatrix" etc using constructor function Diagonal() or Diag(). BUG: rcond() of a singular dpoMatrix gives a LaPack error instead of just 0: MM <- crossprod(M <- Matrix(c(1:4,9:6), 2,4)) ; rcond(MM) ##> Error in rcond(MM) : Lapack routine dpotrf returned error code 4 --- - combine the C functions for multiplication by special forms and solution wrt special forms by using a 'right' argument and a 'classed' argument. [done with dgeMatrix_matrix_mm(); not yet for other classes; and for _crossprod()] - add more comprehensive examples / tests for Schur decomposition - arithmetic for sparse matrices: <sparseMatrix> o <same-dim-sparseMatrix> should return a sparse matrix for at least "+" and "*" , also %%, and "/" and "%/%" at least when the RHS is non-zero a scalar. Challenge: nice implementation (``common non-0''; but Tsparse* is not uniq). --- - Create a Harwell-Boeing version of the matrix mm and the response vector y in inst/external and remove them from the data directory. Modify any examples that use them and modify the Comparisons vignette. - "Math2" , "Math", "Arith": keep triangular and symmetric Matrices when appropriate: particularly desirable for "Math2": round(), signif()

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