Guess the HDF5 datatype of an R object

guess_nelem(x, dtype)

guess_dim(x)

guess_dtype(x, ds_dim = NULL, scalar = FALSE,
  string_len = getOption("hdf5r.default_string_len"))

Arguments

x

The object for which to guess the HDF5 datatype or the dimension or the number of elements

dtype

datatype; used in guessing the number of dataset elements of an r object

ds_dim

Can explicitly set the dimension of the dataset object. For scalar, this is one. Otherwise, this can be used so that a multi-dimensional object can be represented so that some of its dimension are in the dataset, and some are inside an H5T_ARRAY

scalar

Should the datatype be created so that x can be represented as a scalar with that datatype? This is intended to know if a vector/array should be represented as an H5T_ARRAY or not.

string_len

If a string is in the R object, the length to which the corresponding HDF5 type should be set. If it is a positive integer, the string is of that length. If it is Inf, it is variable length. If it is set to estimate, it is set to the length of the longest string in the x.

Value

An object of class H5T that represents the HDF5-type of the Robj that was passed in

Details

Given an object, it creates a datatype in HDF5 that would match this object. For simple datasets like arrays, this function is not so useful, but is very good for creating dataframes or hierarchical objects (like lists of dataframes) etc.

Author

Holger Hoefling