Source code for pytesmo.validation_framework.validation

try:
    from itertools import izip as zip
except ImportError:
    # python 3
    pass

import numpy as np
import pandas as pd
from pygeogrids.grids import CellGrid
import warnings
import logging
from typing import Mapping, Tuple, List

from pytesmo.validation_framework.data_manager import DataManager
from pytesmo.validation_framework.data_manager import get_result_names
from pytesmo.validation_framework.data_manager import get_result_combinations
from pytesmo.validation_framework.data_scalers import DefaultScaler
import pytesmo.validation_framework.temporal_matchers as temporal_matchers
from pytesmo.utils import ensure_iterable
from distutils.version import LooseVersion

import pytesmo.validation_framework.error_handling as eh


[docs]class Validation(object): """ Class for the validation process. Parameters ---------- datasets : dict of dicts or DataManager :Keys: string, datasets names :Values: dict, containing the following fields :py:class:`pytesmo.validation_framework.data_manager.DataManager` 'class': object Class containing the method read_ts for reading the data. 'columns': list List of columns which will be used in the validation process. 'args': list, optional Args for reading the data. 'kwargs': dict, optional Kwargs for reading the data 'grids_compatible': boolean, optional If set to True the grid point index is used directly when reading other, if False then lon, lat is used and a nearest neighbour search is necessary. 'use_lut': boolean, optional If set to True the grid point index (obtained from a calculated lut between reference and other) is used when reading other, if False then lon, lat is used and a nearest neighbour search is necessary. 'lut_max_dist': float, optional Maximum allowed distance in meters for the lut calculation. spatial_ref: string Name of the dataset used as a spatial, temporal and scaling reference. temporal and scaling references can be changed if needed. See the optional parameters ``temporal_ref`` and ``scaling_ref``. metrics_calculators : dict of functions The keys of the dict are tuples with the following structure: (n, k) with n >= 2 and n>=k. n must be equal to the number of datasets now. n is the number of datasets that should be temporally matched to the reference dataset and k is how many columns the metric calculator will get at once. What this means is that it is e.g. possible to temporally match 3 datasets with 3 columns in total and then give the combinations of these columns to the metric calculator in sets of 2 by specifying the dictionary like: .. code:: { (3, 2): metric_calculator} The values are functions that take an input DataFrame with the columns 'ref' for the reference and 'n1', 'n2' and so on for other datasets as well as a dictionary mapping the column names to the names of the original datasets. In this way multiple metric calculators can be applied to different combinations of n input datasets. temporal_matcher: function, optional function that takes a dict of dataframes and a reference_key. It performs the temporal matching on the data and returns a dictionary of matched DataFrames that should be evaluated together by the metric calculator. temporal_window: float, optional Window to allow in temporal matching in days. The window is allowed on both sides of the timestamp of the temporal reference data. Only used with the standard temporal matcher. temporal_ref: string, optional If the temporal matching should use another dataset than the spatial reference as a reference dataset then give the dataset name here. period : list, optional Of type [datetime start, datetime end]. If given then the two input datasets will be truncated to start <= dates <= end. masking_datasets : dict of dictionaries Same format as the datasets with the difference that the `read` method of these datasets has to return pandas.DataFrames with only boolean columns. True means that the observations at this timestamp should be masked and False means that it should be kept. scaling : str or None or class instance - If set then the data will be scaled into the reference space using the method specified by the string using the :py:class:`pytesmo.validation_framework.data_scalers.DefaultScaler` class. - If set to None then no scaling will be performed. - It can also be set to a class instance that implements a ``scale(self, data, reference_index, gpi_info)`` method. See :py:class:`pytesmo.validation_framework.data_scalers.DefaultScaler` for an example. scaling_ref : string, optional If the scaling should be done to another dataset than the spatial reference then give the dataset name here. Methods ------- calc(job) Takes either a cell or a gpi_info tuple and performs the validation. get_processing_jobs() Returns processing jobs that this process can understand. """ def __init__( self, datasets, spatial_ref, metrics_calculators, temporal_matcher=None, temporal_window=1 / 24.0, temporal_ref=None, masking_datasets=None, period=None, scaling="cdf_match", scaling_ref=None, ): if isinstance(datasets, DataManager): self.data_manager = datasets else: self.data_manager = DataManager(datasets, spatial_ref, period) self.temp_matching = temporal_matcher if self.temp_matching is None: warnings.warn( "You are using the default temporal matcher. If you are using " "one of the newer metric calculators " "(PairwiseIntercomparisonMetrics, TripleCollocationMetrics) " "you should probably use `make_combined_temporal_matcher`" " instead. Have a look at the documentation of the metric " "calculators for more info." ) self.temp_matching = temporal_matchers.BasicTemporalMatching( window=temporal_window ).combinatory_matcher self.temporal_ref = temporal_ref if self.temporal_ref is None: self.temporal_ref = self.data_manager.reference_name self.metrics_c = metrics_calculators for n, k in self.metrics_c: if n < len(self.data_manager.datasets.keys()): raise ValueError("n must be equal to the number of datasets") self.masking_dm = None if masking_datasets is not None: # add temporal reference dataset to the masking datasets since it # is necessary for temporally matching the masking datasets to the # common time stamps. Use _reference here to make a clash with the # names of the masking datasets unlikely masking_datasets.update( {"_reference": datasets[self.temporal_ref]} ) self.masking_dm = DataManager( masking_datasets, "_reference", period=period ) if type(scaling) == str: self.scaling = DefaultScaler(scaling) else: self.scaling = scaling self.scaling_ref = scaling_ref if self.scaling_ref is None: self.scaling_ref = self.data_manager.reference_name self.luts = self.data_manager.get_luts()
[docs] def calc( self, gpis, lons, lats, *args, rename_cols=True, only_with_reference=False, handle_errors='raise', ) -> Mapping[Tuple[str], Mapping[str, np.ndarray]]: """ The argument iterables (lists or numpy.ndarrays) are processed one after the other in tuples of the form (gpis[n], lons[n], lats[n], arg1[n], ..). Parameters ---------- gpis: iterable The grid point indices is an identificator by which the spatial reference dataset can be read. This is either a list or a numpy.ndarray or any other iterable containing this indicator. lons: iterable Longitudes of the points identified by the gpis. Has to be the same size as gpis. lats: iterable latitudes of the points identified by the gpis. Has to be the same size as gpis. args: iterables any addiational arguments have to have the same size as the gpis iterable. They are given to the metrics calculators as metadata. Common usage is e.g. the long name or network name of an in situ station. rename_cols : bool, optional Whether to rename the columns to "ref", "k1", ... before passing the dataframe to the metrics calculators. Default is True. only_with_reference : bool, optional If this is enabled, only combinations that include the reference dataset (from the data manager) are calculated. handle_errors: str, optional (default: 'raise') Governs how to handle errors:: * `raise`: If an error occurs during validation, raise exception. * `ignore`: If an error occurs, assign the correct return code to the result template and continue with the next GPI. Returns ------- compact_results : dict of dicts :Keys: result names, combinations of (referenceDataset.column, otherDataset.column) :Values: dict containing the elements returned by metrics_calculator """ handle_errors = handle_errors.lower() error_handling_options = ["raise", "ignore"] assert handle_errors in error_handling_options, ( f"'handle_errors' must be one of {error_handling_options}" ) if len(args) > 0: gpis, lons, lats, args = args_to_iterable( gpis, lons, lats, *args, n=3 ) else: gpis, lons, lats = args_to_iterable(gpis, lons, lats) results = {} for gpi_info in zip(gpis, lons, lats, *args): try: try: df_dict = self.data_manager.get_data( gpi_info[0], gpi_info[1], gpi_info[2] ) except Exception as e: raise eh.DataManagerError( f"Getting the data for gpi {gpi_info} failed with" f" error: {e}") # if no data is available continue with the next gpi if len(df_dict) == 0: raise eh.NoGpiDataError(f"No data for gpi {gpi_info}") matched_data, result, used_data = self.perform_validation( df_dict, gpi_info, rename_cols=rename_cols, only_with_reference=only_with_reference, handle_errors=handle_errors, ) except Exception as e: if handle_errors == 'raise': raise e elif handle_errors == "ignore": logging.error(f"{gpi_info}: {e}") result = self.dummy_validation_result( gpi_info, rename_cols=rename_cols, only_with_reference=only_with_reference) if isinstance(e, eh.ValidationError): retcode = e.return_code else: retcode = eh.VALIDATION_FAILED for key in result: result[key][0]["status"][0] = retcode # add result of one gpi to global results dictionary for r in result: if r not in results: results[r] = [] results[r] = results[r] + result[r] # So far, results is a dictionary mapping from a validation name/key # (the involved datasets) to lists of individual result dictionaries # for each gpi. # Here, these lists are summarized to have a single dictionary of numpy # arrays for each validation key compact_results = {} for key in results.keys(): compact_results[key] = {} for field_name in results[key][0].keys(): entries = [] for result in results[key]: entries.append(result[field_name][0]) compact_results[key][field_name] = np.array( entries, dtype=results[key][0][field_name].dtype ) return compact_results
[docs] def perform_validation( self, df_dict, gpi_info, rename_cols=True, only_with_reference=False, handle_errors="raise", ) -> Mapping[Tuple[str], List[Mapping[str, np.ndarray]]]: """ Perform the validation for one grid point index and return the matched datasets as well as the calculated metrics. Parameters ---------- df_dict: dict of pandas.DataFrames DataFrames read by the data readers for each dataset gpi_info: tuple tuple of at least, (gpi, lon, lat) rename_cols : bool, optional Whether to rename the columns to "ref", "k1", ... before passing the dataframe to the metrics calculators. Default is True. only_with_reference: bool, optional (default: False) Only compute metrics for dataset combinations where the reference is included. Returns ------- matched_n: dict of pandas.DataFrames temporally matched data stored by (n, k) tuples results: dict Dictonary of calculated metrics stored by dataset combinations tuples. used_data: dict The DataFrame used for calculation of each set of metrics. Raises ------ eh.TemporalMatchingError : If temporal matching failed eh.NoTempMatchedDataError : If there is insufficient data or the temporal matching did not return data. eh.ScalingError : If scaling failed """ results = {} used_data = {} matched_n = {} if self.masking_dm is not None: ref_df = df_dict[self.temporal_ref] masked_ref_df = self.mask_dataset(ref_df, gpi_info) if len(masked_ref_df) == 0: return matched_n, results, used_data df_dict[self.temporal_ref] = masked_ref_df # we only need the data columns data_df_dict = {} for ds in df_dict: columns = self.data_manager.datasets[ds]["columns"] data_df_dict[ds] = df_dict[ds][columns] # matched_n is a dictionary mapping from dataset combinations as keys # to pandas dataframes try: matched_n = self.temporal_match_datasets(data_df_dict) except Exception: raise eh.TemporalMatchingError( f"Temporal matching failed for gpi {gpi_info}!" ) for n, k in self.metrics_c: metrics_calculator = self.metrics_c[(n, k)] def dummy_result(): # to get only an empty template returned, we pass an # empty dataframe here, with the correct column names dummy_df = pd.DataFrame([], columns=result_ds_names) metrics = metrics_calculator(dummy_df, gpi_info) return metrics n_matched_data = matched_n[(n, k)] if len(n_matched_data) == 0: # this would happen if self.temp_matching returns an empty list # or dictionary for n=n, k=k raise eh.NoTempMatchedDataError( f"No temporally matched data for ({n}, {k})" f" and metric calculator {self.metrics_c[(n,k)]}" f" for gpi {gpi_info}!" ) result_names = get_result_combinations( self.data_manager.ds_dict, n=k ) for data, result_key in self.k_datasets_from( n_matched_data, result_names ): # it might also be a good idea to move this to # `get_result_combinations` result_ds_names = [key[0] for key in result_key] if only_with_reference: if self.data_manager.reference_name not in result_ds_names: continue if result_key not in results.keys(): results[result_key] = [] if len(data) == 0: if handle_errors == "raise": raise eh.NoTempMatchedDataError( f"Temporal matching resulted in empty dataset for" f" {result_key} for gpi {gpi_info}" ) else: metrics = dummy_result() metrics["status"][0] = eh.NO_TEMP_MATCHED_DATA results[result_key].append(metrics) continue # at this stage we can drop the column multiindex and just use # the dataset name if LooseVersion(pd.__version__) < LooseVersion("0.23"): data.columns = data.columns.droplevel(level=1) else: data = data.rename(columns=lambda x: x[0]) if self.scaling is not None: # get scaling index by finding the column in the # DataFrame that belongs to the scaling reference scaling_index = data.columns.tolist().index( self.scaling_ref ) try: data = self.scaling.scale( data, scaling_index, gpi_info ) except Exception as e: raise eh.ScalingError( f"Scaling failed for {result_key} for gpi" f" {gpi_info} with error {e}!" ) # Drop the scaling reference if it was not in the intended # results if self.scaling_ref not in [key[0] for key in result_key]: data = data.drop(columns=[self.scaling_ref]) # Rename the columns to 'ref', 'k1', 'k2', ... if rename_cols: rename_dict = {} for i, r in enumerate(result_key): rename_dict[r[0]] = f"k{i}" if i > 0 else "ref" data.rename(columns=rename_dict, inplace=True) used_data[result_key] = data try: metrics = metrics_calculator(data, gpi_info) except Exception: if handle_errors == "raise": raise eh.MetricsCalculationError( f"Metrics calculation failed for {result_key}" f" for gpi {gpi_info}!" ) else: metrics = dummy_result() metrics["status"][0] = eh.METRICS_CALCULATION_FAILED results[result_key].append(metrics) return matched_n, results, used_data
[docs] def dummy_validation_result( self, gpi_info, rename_cols=True, only_with_reference=False, ) -> Mapping[Tuple[str], List[Mapping[str, np.ndarray]]]: """ Creates an empty result dictionary to be used if perform_validation fails """ results = {} for n, k in self.metrics_c: result_names = get_result_combinations( self.data_manager.ds_dict, n=k ) for result_key in result_names: # it might also be a good idea to move this to # `get_result_combinations` result_ds_names = [key[0] for key in result_key] if only_with_reference: if self.data_manager.reference_name not in result_ds_names: continue metrics_calculator = self.metrics_c[(n, k)] # to get only an empty template returned, we pass an empty # dataframe here, with the correct column names dummy_df = pd.DataFrame([], columns=result_ds_names) metrics = metrics_calculator(dummy_df, gpi_info) if result_key not in results.keys(): results[result_key] = [] results[result_key].append(metrics) return results
[docs] def mask_dataset(self, ref_df, gpi_info): """ Mask the temporal reference dataset with the data read through the masking datasets. Parameters ---------- gpi_info: tuple tuple of at least, (gpi, lon, lat) Returns ------- mask: numpy.ndarray boolean array of the size of the temporal reference read """ matched_masking = self.temporal_match_masking_data(ref_df, gpi_info) # this will only be one element since n is the same as the # number of masking datasets result_names = get_result_names( self.masking_dm.ds_dict, "_reference", n=2 ) choose_all = pd.DataFrame(index=ref_df.index) for data, result in self.k_datasets_from( matched_masking, result_names, include_scaling_ref=False ): if len(data) == 0: continue for key in result: if key[0] != "_reference": # this is necessary since the boolean datatype might have # been changed to float 1.0 and 0.0 issue with temporal # resampling that is not easily resolved since most # datatypes have no nan representation. choose = pd.Series((data[key] is False), index=data.index) choose = choose.reindex( index=choose_all.index, fill_value=True ) choose_all[key] = choose.copy() choosing = choose_all.apply(np.all, axis=1) return ref_df[choosing]
[docs] def temporal_match_masking_data(self, ref_df, gpi_info): """ Temporal match the masking data to the reference DataFrame Parameters ---------- ref_df: pandas.DataFrame Reference data gpi_info: tuple or list contains, (gpi, lon, lat) Returns ------- matched_masking: dict of pandas.DataFrames Contains temporally matched masking data. This dict has only one key being a tuple that contains the matched datasets. """ # read only masking datasets and use the already read reference masking_df_dict = self.masking_dm.get_other_data( gpi_info[0], gpi_info[1], gpi_info[2] ) masking_df_dict.update({"_reference": ref_df}) matched_masking = self.temp_matching( masking_df_dict, "_reference", n=2 ) return matched_masking
[docs] def temporal_match_datasets(self, df_dict): """ Temporally match all the requested combinations of datasets. Parameters ---------- df_dict: dict of pandas.DataFrames DataFrames read by the data readers for each dataset Returns ------- matched_n: dict of pandas.DataFrames for each (n, k) in the metrics calculators the n temporally matched dataframes """ matched_n = {} for n, k in self.metrics_c: matched_data = self.temp_matching( df_dict, self.temporal_ref, n=n, k=k ) matched_n[(n, k)] = matched_data return matched_n
[docs] def k_datasets_from( self, n_matched_data, result_names, include_scaling_ref=True ): """ Extract k datasets from n temporally matched ones. This is used to send combinations of k datasets to metrics calculators expecting only k datasets. Parameters ---------- n_matched_data: dict of pandas.DataFrames DataFrames in which n datasets were temporally matched. The key is a tuple of the dataset names. result_names: list result names to extract include_scaling_ref: boolean, optional if set the scaling reference will always be included. Should only be disabled for getting the masking datasets Yields ------ data: pd.DataFrame pandas DataFrame with k columns extracted from the temporally matched datasets result: tuple Tuple describing which datasets and columns are in the returned data. ((dataset_name, column_name), (dataset_name2, column_name2)) """ for result in result_names: result_extract = result if self.scaling is not None and include_scaling_ref: # always make sure the scaling reference is included in the # results otherwise the scaling will fail scaling_ref_column = self.data_manager.datasets[ self.scaling_ref ]["columns"][0] scaling_result_name = (self.scaling_ref, scaling_ref_column) if scaling_result_name not in result: result_extract = result + (scaling_result_name,) data = self.get_data_for_result_tuple( n_matched_data, result_extract ) yield data, result
[docs] def get_data_for_result_tuple(self, n_matched_data, result_tuple): """ Extract a dataframe for a given result tuple from the matched dataframes. Parameters ---------- n_matched_data: dict of pandas.DataFrames DataFrames in which n datasets were temporally matched. The key is a tuple of the dataset names. result_tuple: tuple Tuple describing which datasets and columns should be extracted. ((dataset_name, column_name), (dataset_name2, column_name2)) Returns ------- data: pd.DataFrame pandas DataFrame with columns extracted from the temporally matched datasets """ # find the key into the temporally matched dataset by combining the # dataset parts of the result_names dskey = [] for i, r in enumerate(result_tuple): dskey.append(r[0]) dskey = tuple(dskey) if len(list(n_matched_data)[0]) == len(dskey): # we should have an exact match of datasets and # temporal matches # still need to make sure that dskey is in the right order and # contains all the same datasets as the n_matched_data for key in n_matched_data: if sorted(dskey) == sorted(key): dskey = key break if dskey not in n_matched_data: return [] else: data = n_matched_data[dskey] else: # more datasets were temporally matched than are # requested now so we select a temporally matched # dataset that has the first key in common with the # temporal reference. # This guarantees that we only select columns from dataframes for # which the temporal reference dataset was included in the # temporal matching first_match = [ key for key in n_matched_data if self.temporal_ref == key[0] ] found_key = None for key in first_match: for dsk in dskey: if dsk not in key: continue found_key = key data = n_matched_data[found_key] # extract only the relevant columns from matched DataFrame data = data[[x for x in result_tuple]] # drop values if one column is NaN data = data.dropna() return data
[docs] def get_processing_jobs(self): """ Returns processing jobs that this process can understand. Returns ------- jobs : list List of cells or gpis to process. """ jobs = [] if self.data_manager.reference_grid is not None: if type(self.data_manager.reference_grid) is CellGrid: cells = self.data_manager.reference_grid.get_cells() for cell in cells: ( cell_gpis, cell_lons, cell_lats, ) = self.data_manager.reference_grid.grid_points_for_cell( cell ) jobs.append([cell_gpis, cell_lons, cell_lats]) else: ( gpis, lons, lats, ) = self.data_manager.reference_grid.get_grid_points() jobs = [gpis, lons, lats] return jobs
[docs]def args_to_iterable(*args, **kwargs): """ Convert arguments to iterables. Parameters ---------- args: iterables or not arguments n : int, optional number of explicit arguments """ if "n" in kwargs: n = kwargs["n"] else: n = len(args) arguments = [] for i, arg in enumerate(args): arguments.append(ensure_iterable(arg)) it = iter(arguments) for _ in range(n): yield next(it, None) if n < len(args): yield tuple(it)