R/update.online_lm.R

In blakeboswell/millerlsqr: Not a package

update.online_lm <- function(object, moredata, ...) {
    
  mf <- model.frame(object$terms, moredata)
  mm <- model.matrix(object$terms, mf)
  
  if (is.null(object$weights)) {
    w <- NULL
  } else {
    w <- model.frame(object$weights, moredata)[[1]]
  }

  if (!identical(object$assign, attr(mm, "assign"))) {
    stop("model matrices incompatible")
  }
      
  if (is.null(off <- model.offset(mf))) {
    off <- 0
  }

  update.online_qr(object$qr, mm, model.response(mf) - off, w)
  object$n <- object$n + nrow(mm)
    
  if (!is.null(object$sandwich)) {
    
    p  <- ncol(mm)
    n  <- nrow(mm)
    xx <- matrix(nrow = n, ncol = p * (p + 1))
    xx[, 1:p] <- mm * (model.response(mf) - off)
    for (i in 1:p) {
      xx[, p * i + (1:p)] <- mm * mm[, i]
    }
    xyqr <- update(object$sandwich$xy, xx, rep(0, n), w * w)
    object$sandwich <- list(xy = xyqr)
    
  }
  object
}