Re: [sqlite] sparse matrix in scientific computing with sqlite

Michael Chen wrote: > --this is my first version for the purpose of storing sparse numerical > matrix in sql > --please let me know how to fix the bug at the end of the file, and how to > tune the performance > --or any better reference, thanks! > > .explain--

Re: [sqlite] sparse matrix in scientific computing with sqlite

yes, that's what I am thinking of too. This big table is in charge of store all matrix, keep track of all index changes, and rollback when needed. I will only extract a tiny part from this big table in format like a sparse matrix, and put it in C array, then the available numerical routines, such

Re: [sqlite] sparse matrix in scientific computing with sqlite

On Fri, Oct 16, 2009 at 1:41 PM, Michael Chen wrote: > rdbms is indeed not a place for store a single sparse matrix like this. > However I have hundreds of them, and I need to break them and recombine them > frequently; furthermore, I need to drop a few rows or

Re: [sqlite] sparse matrix in scientific computing with sqlite

rdbms is indeed not a place for store a single sparse matrix like this. However I have hundreds of them, and I need to break them and recombine them frequently; furthermore, I need to drop a few rows or columns successively, and need to be able to trace back what's a row's original index. I think

Re: [sqlite] sparse matrix in scientific computing with sqlite

thanks Pavel ! On Fri, Oct 16, 2009 at 1:24 PM, Pavel Ivanov wrote: > > -- IA = [ 1 3 5 7 ] // IA(i) = Index of the first nonzero element > of > > row i in A > > Why 4th element if A has only 3 rows? > > > create temp view rowwiseC as > > select a1.rowid, sum(a2.ct) +1