Add rbind and cbind methods for mmMatrix about bgdata HOT 5 CLOSED

Another option, instead of manually adding chunks to an existing mmMatrix, would be to create a whole new one that combines all input parameters of rbind or cbind. This would allow for both functions to be easily implemented and for multiple mmMatrix arguments, and also result in leaner chunking (our main overhead).

from bgdata.

We also have to decide whether to get the current storage location of an mmMatrix via an attribute of the mmMatrix (which impacts portability as we cannot always guarantee accuracy of that value since an mmMatrix can be loaded directly using load) or as a separate parameter (which would be unusual for an *bind method).

from bgdata.

Looks like additional parameters can be added to the *bind methods. vmode, folderOut, nChunks, and dimorder would be nice.

from bgdata.

Here's an initial draft for rbind for rmmMatrix:

rbind.rmmMatrix<-function(...,vmode='byte',folderOut=NULL,nChunks=NULL,dimorder=c(2,1),deparse.level=1){
    allargs<-list(...)
    alldims<-unique(sapply(allargs,function(arg){
        dims<-dim(arg)
        if(is.null(dims)){
            c(1, length(arg))
        }else{
            dims
        }
    }))
    numcols<-unique(alldims[2,])
    if(length(numcols)>1){
        stop('all params need the same number of columns')
    }
    numrows<-sum(alldims[1,])
    mmmatrix<-rmmMatrix(nrow=numrows,ncol=numcols,vmode=vmode,folderOut=folderOut,nChunks=nChunks,dimorder=dimorder)
    currow<-1
    for(arg in 1:ncol(alldims)){
        argrows<-alldims[1,arg]
        for(argrow in 1:argrows){
            if(argrows>1){
                mmmatrix[currow,]<-allargs[[arg]][argrow,]
            }else{
                mmmatrix[currow,]<-allargs[[arg]]
            }
            currow<-currow+1
        }
    }
    mmmatrix
}

Let me know what you think. In the meantime I will time it out for larger matrices. There is are some possible performance improvements when copying more than one row at the same time.

from bgdata.

I'll reopen this in the LinkedMatrix repository.

from bgdata.