h2o (version 2.8.4.4)

h2o.importFolder: Import Local Directory of Data Files

Description

Imports all the files in the local directory and parses them, concatenating the data into a single H2O data matrix and returning an object containing the identifying hex key.

Usage

h2o.importFolder(object, path, pattern = "", key = "", parse = TRUE, header,
  header_with_hash, sep = "", col.names, parser_type="AUTO")

Arguments

object

An H2OClient object containing the IP address and port of the server running H2O.

path

The path of the folder directory to be imported. Each row of data appears as one line of the file. If it does not contain an absolute path, the file name is relative to the current working directory.

key

(Optional) The unique hex key assigned to the imported file. If none is given, a key will automatically be generated based on the file path.

pattern

(Optional) Character string containing a regular expression to match file(s) in the folder.

parse

(Optional) A logical value indicating whether the file should be parsed after import.

header

(Optional) A logical value indicating whether the first row is the column header. If missing, H2O will automatically try to detect the presence of a header.

header_with_hash

(Optional) A logical value indicating whether the first row is a column header that starts with a hash character. If missing, H2O will automatically try to detect the presence of a header.

sep

(Optional) The field separator character. Values on each line of the file are separated by this character. If sep = "", the parser will automatically detect the separator.

col.names

(Optional) An H2OParsedData object containing a single delimited line with the column names for the file.

parser_type

(Optional) Specify the type of data to be parsed. parser_type = "AUTO" is the default, other acceptable values are "SVMLight", "XLS", and "CSV".

Value

• If parse = TRUE, the function returns an object of class H2OParsedData. Otherwise, when parse = FALSE, it returns an object of class H2ORawData.

Details

This method imports all the data files in a given folder and concatenates them together row-wise into a single matrix represented by a H2OParsedData object. The data files must all have the same number of columns, and the columns must be lined up in the same order, otherwise an error will be returned.

WARNING: In H2O, import is lazy! Do not modify the data files on hard disk until after parsing is complete.

See Also

h2o.importFile, h2o.importHDFS, h2o.importURL, h2o.uploadFile

Examples

library(h2o)
localH2O = h2o.init()
myPath = system.file("extdata", "prostate_folder", package = "h2o")
prostate_all.hex = h2o.importFolder(localH2O, path = myPath)
class(prostate_all.hex)
summary(prostate_all.hex)