naresid(omit, x, ...)
napredict(omit, x, ...)na.action function,
    typically the "na.action" attribute of the result of
    na.omit or na.exclude.x.
predict,
  fitted and residuals methods for modelling
  functions to compensate for the removal of NAs in the fitting
  process.  They are used by the default, "lm", "glm" and
  "nls" methods, and by further methods in packages \href{https://CRAN.R-project.org/package=#1}{\pkg{#1}}MASSMASS,
  \href{https://CRAN.R-project.org/package=#1}{\pkg{#1}}rpartrpart and \href{https://CRAN.R-project.org/package=#1}{\pkg{#1}}survivalsurvival.  Also used for the scores returned by
  factanal, prcomp and princomp.  The default methods do nothing.  The default method for the na.exclude
  action is to pad the object with NAs in the correct positions to
  have the same number of rows as the original data frame.
  Currently naresid and napredict are identical, but
  future methods need not be.  naresid is used for residuals, and
  napredict for fitted values, predictions and weights.