Source code for easyvvuq.decoders.hdf5
"""A Decoder for HDF5 format files.
"""
import os
import logging
import h5py
from easyvvuq import OutputType
__copyright__ = """
Copyright 2018 Robin A. Richardson, David W. Wright
This file is part of EasyVVUQ
EasyVVUQ is free software: you can redistribute it and/or modify
it under the terms of the Lesser GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
EasyVVUQ is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
Lesser GNU General Public License for more details.
You should have received a copy of the Lesser GNU General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>.
"""
__license__ = "LGPL"
logger = logging.Logger(__name__)
[docs]class HDF5:
"""HDF5 Decoder.
Parameters
----------
target_filename: str
Filename of an HDF5 file to decode.
ouput_columns: list
A list of column names that will be selected to appear in the output.
"""
def __init__(self, target_filename, output_columns):
if len(output_columns) == 0:
msg = "output_columns cannot be empty."
logger.error(msg)
raise RuntimeError(msg)
self.target_filename = target_filename
self.output_columns = output_columns
self.output_type = OutputType('sample')
@staticmethod
def _get_output_path(run_info=None, outfile=None):
"""Constructs absolute path from the `target_filename` and the `run_dir` parameter
in the `run_info` retrieved from the database.
Parameters
----------
run_info: dict
Run info as retrieved from the database.
outfile: str
Filename of the file to be parsed.
Returns
-------
str
An absolute path to the output file in the run directory.
"""
run_path = run_info['run_dir']
if not os.path.isdir(run_path):
raise RuntimeError(f"Run directory does not exist: {run_path}")
return os.path.join(run_path, outfile)
[docs] def parse_sim_output(self, run_info={}):
"""Parses the HDF5 file and converts it to the EasyVVUQ internal dictionary based
format. The file is parsed in such a way that each column will appear as a vector
QoI in the output dictionary.
For example if the file contains the following data
a,b
1,2
3,4
And both `a` and `b` are specified as `output_columns` the output will look as follows
{'a': [1, 3], 'b': [2, 4]}.
Parameters
----------
run_info: dict
Information about the run (used to retrieve construct the absolute path
to the CSV file that needs decoding.
"""
out_path = self._get_output_path(run_info, self.target_filename)
results = {}
with h5py.File(out_path, 'r') as h5f:
for column in self.output_columns:
try:
# TODO: this will always flatten, but HDF5 could handle
# 2D or 3D arrays as well. Will probably break the analysis
# classes though, but maybe something to incorporate later.
results[column] = h5f[column][()].flatten().tolist()
except KeyError:
raise RuntimeError('column not found in the hdf5 file: {}'.format(column))
return results