Source code for mpas_analysis.shared.time_series.time_series

# This software is open source software available under the BSD-3 license.
#
# Copyright (c) 2019 Triad National Security, LLC. All rights reserved.
# Copyright (c) 2019 Lawrence Livermore National Security, LLC. All rights
# reserved.
# Copyright (c) 2019 UT-Battelle, LLC. All rights reserved.
#
# Additional copyright and license information can be found in the LICENSE file
# distributed with this code, or at
# https://raw.githubusercontent.com/MPAS-Dev/MPAS-Analysis/master/LICENSE
"""
Utility functions related to time-series data sets
"""
# Authors
# -------
# Xylar Asay-Davis

from __future__ import absolute_import, division, print_function, \
    unicode_literals

import xarray as xr
import numpy
import os
from distutils.spawn import find_executable
import glob
import subprocess
from six import string_types

from mpas_analysis.shared.timekeeping.utility import days_to_datetime


def combine_time_series_with_ncrcat(inFileNames, outFileName,
                                    variableList=None, logger=None):
    # {{{
    '''
    Uses ncrcat to extact time series from a series of files

    inFileNames : str or list of str
        A file name with wildcard(s) or a list of input files from which to
        extract the time series.

    outFileName : str
        The output NetCDF file where the time series should be written.

    variableList : list of str, optional
        A list of varibles to include.  All variables are included by default

    logger : `logging.Logger``, optional
        A logger to which ncclimo output should be redirected

    Raises
    ------
    OSError
        If ``ncrcat`` is not in the system path.

    Author
    ------
    Xylar Asay-Davis
    '''

    if find_executable('ncrcat') is None:
        raise OSError('ncrcat not found. Make sure the latest nco '
                      'package is installed: \n'
                      'conda install nco\n'
                      'Note: this presumes use of the conda-forge '
                      'channel.')

    if os.path.exists(outFileName):
        return

    if isinstance(inFileNames, string_types):
        inFileNames = sorted(glob.glob(inFileNames))

    args = ['ncrcat', '-4', '--record_append', '--no_tmp_fl']

    if variableList is not None:
        args.extend(['-v', ','.join(variableList)])

    printCommand = '{} {} ... {} {}'.format(' '.join(args), inFileNames[0],
                                            inFileNames[-1],
                                            outFileName)
    args.extend(inFileNames)
    args.append(outFileName)

    if logger is None:
        print('running: {}'.format(printCommand))
    else:
        logger.info('running: {}'.format(printCommand))
        for handler in logger.handlers:
            handler.flush()
    process = subprocess.Popen(args, stdout=subprocess.PIPE,
                               stderr=subprocess.PIPE)
    stdout, stderr = process.communicate()

    if stdout:
        stdout = stdout.decode('utf-8')
        for line in stdout.split('\n'):
            if logger is None:
                print(line)
            else:
                logger.info(line)
    if stderr:
        stderr = stderr.decode('utf-8')
        for line in stderr.split('\n'):
            if logger is None:
                print(line)
            else:
                logger.error(line)

    if process.returncode != 0:
        raise subprocess.CalledProcessError(process.returncode,
                                            ' '.join(args))

    # }}}


[docs]def cache_time_series(timesInDataSet, timeSeriesCalcFunction, cacheFileName, calendar, yearsPerCacheUpdate=1, logger=None): # {{{ ''' Create or update a NetCDF file ``cacheFileName`` containing the given time series, calculated with ``timeSeriesCalcFunction`` over the given times, start and end year, and time frequency with which results are cached. Note: only works with climatologies where the mask (locations of ``NaN`` values) doesn't vary with time. Parameters ---------- timesInDataSet : array-like Times at which the time series is to be calculated, typically taken from ``ds.Times.values`` for a data set from which the time series will be extracted or computed. timeSeriesCalcFunction : function A function with arguments ``timeIndices``, indicating the entries in ``timesInDataSet`` to be computed, and ``firstCall``, indicating whether this is the first call to the funciton (useful for printing progress information). cacheFileName : str The absolute path to the cache file where the times series will be stored calendar : ``{'gregorian', 'gregorian_noleap'}`` The name of one of the calendars supported by MPAS cores, used to determine ``year`` and ``month`` from ``Time`` coordinate yearsPerCacheUpdate : int, optional The frequency with which the cache file is updated as the computation progresses. If the computation is expensive, it may be useful to output the file frequently. If not, there will be needless overhead in caching the file too frequently. logger : ``logging.Logger``, optional A logger to which to write output as the time series is computed Returns ------- climatology : object of same type as ``ds`` A data set without the ``'Time'`` coordinate containing the mean of ds over all months in monthValues, weighted by the number of days in each month. ''' # Authors # ------- # Xylar Asay-Davis timesProcessed = numpy.zeros(len(timesInDataSet), bool) # figure out which files to load and which years go in each file continueOutput = os.path.exists(cacheFileName) cacheDataSetExists = False if continueOutput: if logger is not None: logger.info(' Read in previously computed time series') # read in what we have so far try: dsCache = xr.open_dataset(cacheFileName, decode_times=False) cacheDataSetExists = True except IOError: # assuming the cache file is corrupt, so deleting it. message = 'Deleting cache file {}, which appears to have ' \ 'been corrupted.'.format(cacheFileName) if logger is None: print('Warning: {}'.format(message)) else: logger.warning(message) os.remove(cacheFileName) if cacheDataSetExists: # force loading and then close so we can overwrite the file later dsCache.load() dsCache.close() for time in dsCache.Time.values: timesProcessed[timesInDataSet == time] = True datetimes = days_to_datetime(timesInDataSet, calendar=calendar) yearsInDataSet = numpy.array([date.year for date in datetimes]) startYear = yearsInDataSet[0] endYear = yearsInDataSet[-1] firstProcessed = True for firstYear in range(startYear, endYear + 1, yearsPerCacheUpdate): years = range(firstYear, numpy.minimum(endYear + 1, firstYear + yearsPerCacheUpdate)) mask = numpy.zeros(len(yearsInDataSet), bool) for year in years: mask = numpy.logical_or(mask, yearsInDataSet == year) mask = numpy.logical_and(mask, numpy.logical_not(timesProcessed)) timeIndices = numpy.nonzero(mask)[0] if len(timeIndices) == 0: # no unprocessed time entries in this data range continue if logger is not None: if firstProcessed: logger.info(' Process and save time series') if yearsPerCacheUpdate == 1: logger.info(' {:04d}'.format(years[0])) else: logger.info(' {:04d}-{:04d}'.format(years[0], years[-1])) ds = timeSeriesCalcFunction(timeIndices, firstProcessed) firstProcessed = False if cacheDataSetExists: dsCache = xr.concat([dsCache, ds], dim='Time') # now sort the Time dimension: dsCache = dsCache.loc[{'Time': sorted(dsCache.Time.values)}] else: dsCache = ds cacheDataSetExists = True dsCache.to_netcdf(cacheFileName) return dsCache.sel(Time=slice(timesInDataSet[0], timesInDataSet[-1]))
# }}} # vim: foldmethod=marker ai ts=4 sts=4 et sw=4 ft=python