Import multiple files

The import_file (Python)/importFolder (R) function can be used to import multiple local files by specifying a directory and a pattern. Example patterns include:

  • pattern="/A/.*/iris_.*": Import all files that have the pattern /A/.*/iris_.* in the specified directory.

  • pattern="/A/iris_.*": Import all files that have the pattern /A/iris_.* in the specified directory.

  • pattern="/A/B/iris_.*": Import all files that have the pattern /A/B/iris_.* in the specified directory.

  • pattern="iris_.*": Import all files that have the pattern iris_.* in the specified directory.

Note

  • All files that are specified to be included must have the same number and set of columns.

  • When parsing a data file containing timestamps that do not include a timezone, the timestamps will be interpreted as UTC (GMT). You can override the parsing timezone using the following:

    • Python: h2o.cluster().timezone = "America/Los Angeles"

    • R: h2o.setTimezone("America/Los Angeles")

Attention

The following examples assume that you’ve cloned the H2O-3 GitHub repository and that the following command was run in the h2o-3 folder to retrieve the smalldata datasets:

./gradlew syncSmalldata

Python

R

# To import all .csv files from an anomaly folder stored locally matching the regex ".*\.csv"
import h2o
h2o.init()
ecg_pattern = h2o.import_file(path="../path_to_h2o-3/smalldata/anomaly/",pattern = ".*\.csv")

# To import all .csv files from the prostate_folder directory:
library(h2o)
h2o.init()
pros_path <- system.file("extdata", "prostate_folder", package = "h2o")
prostate_pattern <- h2o.importFolder(path = pros_path,
                                     pattern = ".*.csv")
class(prostate_pattern)
summary(prostate_pattern)

# To import all .csv files from an anomaly folder stored locally
ecg_path <- "../path_to_h2o-3/smalldata/anomaly/"
ecg_pattern <- h2o.importFolder(path = ecg_path,
                                pattern = ".*.csv")

class(ecg_pattern)
summary(ecg_pattern)