R/h5_utils.r

In RBigData/shff: Sparse HDF5 File Format

close_and_stop = function(h5_fp, msg)
{
  h5close(h5_fp)
  stop(msg, call.=FALSE)
}



h5_check_dataset = function(h5_fp, dataset)
{
  if (existsGroup(dataset))
    close_and_stop(h5_fp, "dataset already exists in h5 file")
  
  invisible()
}



h5_get_dataset = function(h5_fp, dataset)
{
  if (is.null(dataset))
  {
    datasets = names(h5_fp)
    if (length(datasets) != 1)
    {
      h5close(h5_fp)
      stop("multiple datasets available")
    }
    else
      dataset = datasets[1]
  }
  
  dataset
}



h5_detect_format = function(h5_fp, dataset, verbose=FALSE)
{
  if (isTRUE(verbose))
    cat("detecting format...")
  
  attrs = h5attributes(h5_fp)
  
  if (!is.null(attrs$SHFF_VERSION))
    fmt = "shff"
  else
    fmt = "unknown"
  
  if (isTRUE(verbose))
    cat(fmt, "\n")
  
  fmt
}