R/FLSV.R

In Fuzzy-Logix/AdapteR: Converts R syntax to SQL to provide fast analytics using in-database C++ library DB Lytix.

#' @include FLMatrix.R
NULL

#' Singular Values of a FLMatrix.
#'
#' \code{FLSV} computes the singular values for FLMatrix objects.
#'
#' @param object is of class FLMatrix
#' @param ... any additional arguments
#' @section Constraints:
#' Input can only be a square matrix (n x n) with maximum dimension limitations
#' of (700 x 700).
#' @return \code{FLSV} returns a FLVector object representing the singular values.
#' @examples
#' flmatrix <- FLMatrix("tblMatrixMulti", 5,"MATRIX_ID","ROW_ID","COL_ID","CELL_VAL")
#' resultFLVector <- FLSV(flmatrix)
#' @export
FLSV <- function (object, ...){
  UseMethod("FLSV", object)
}

#' @export
FLSV.FLMatrix<-function(object,...)
{
	#checkSquare(object)
	# connection<-getFLConnection(object)
    ## flag3Check(connection)

	# sqlstr<-paste0(viewSelectMatrix(object,"a",withName="z"),
 #                   outputSelectMatrix("FLSVUdt",includeMID=FALSE,
 #                   	outColNames=list(vectorIdColumn="'%insertIDhere%'",
 #                                     vectorIndexColumn="OutputID",
 #                                     vectorValueColumn="OutputSV"),
 #                    viewName="z",localName="a",vconnection=connection)
 #                   )
    
     sqlstr <- constructMatrixUDTSQL(pObject=object,
                                    pFuncName="FLSVUdt",
                                    pdims=getDimsSlot(object),
                                    pdimnames=dimnames(object),
                                    pWhereConditions=list(...)[["pWhereConditions"]],
                                    pReturnQuery=TRUE
                                    )

	tblfunqueryobj <- new("FLTableFunctionQuery",
                        connectionName = attr(connection,"name"),
                        variables = list(
                      obs_id_colname = "vectorIndexColumn",
                      cell_val_colname = "vectorValueColumn"),
                        whereconditions="",
                        order = "",
                        SQLquery=sqlstr)

  flv <- newFLVector(
        select = tblfunqueryobj,
        Dimnames = list(1:nrow(object),
                        "vectorValueColumn"),
        isDeep = FALSE)

  return(ensureQuerySize(pResult=flv,
              pInput=list(object),
              pOperator="FLSV",
              pStoreResult=TRUE))
}