from pathlib import Path
from typing import Dict, Optional, Tuple, Union
from openghg.types import optionalPathType
from pandas import DataFrame, Timedelta
[docs]
def parse_crds(
data_filepath: Union[str, Path],
site: str,
network: str,
inlet: Optional[str] = None,
instrument: Optional[str] = None,
sampling_period: Optional[Union[str, float, int]] = None,
measurement_type: Optional[str] = None,
drop_duplicates: bool = True,
update_mismatch: str = "never",
site_filepath: optionalPathType = None,
**kwargs: Dict,
) -> Dict:
"""Parses a CRDS data file and creates a dictionary of xarray Datasets
ready for storage in the object store.
Args:
data_filepath: Path to file
site: Three letter site code
network: Network name
inlet: Inlet height
instrument: Instrument name
sampling_period: Sampling period in seconds
measurement_type: Measurement type e.g. insitu, flask
drop_duplicates: Drop measurements at duplicate timestamps, keeping the first.
update_mismatch: This determines how mismatches between the internal data
"attributes" and the supplied / derived "metadata" are handled.
This includes the options:
- "never" - don't update mismatches and raise an AttrMismatchError
- "from_source" / "attributes" - update mismatches based on input data (e.g. data attributes)
- "from_definition" / "metadata" - update mismatches based on associated data (e.g. site_info.json)
site_filepath: Alternative site info file (see openghg/supplementary_data repository for format).
Otherwise will use the data stored within openghg_defs/data/site_info JSON file by default.
Returns:
dict: Dictionary of gas data
"""
from pathlib import Path
from openghg.standardise.meta import assign_attributes
from openghg.util import format_inlet
if not isinstance(data_filepath, Path):
data_filepath = Path(data_filepath)
inlet = format_inlet(inlet)
# This may seem like an almost pointless function as this is all we do
# but it makes it a lot easier to test assign_attributes
gas_data = _read_data(
data_filepath=data_filepath,
site=site,
network=network,
inlet=inlet,
instrument=instrument,
sampling_period=sampling_period,
measurement_type=measurement_type,
drop_duplicates=drop_duplicates,
)
# Ensure the data is CF compliant
gas_data = assign_attributes(
data=gas_data,
site=site,
sampling_period=sampling_period,
update_mismatch=update_mismatch,
site_filepath=site_filepath,
)
return gas_data
def _read_data(
data_filepath: Path,
site: str,
network: str,
inlet: Optional[str] = None,
instrument: Optional[str] = None,
sampling_period: Optional[Union[str, float, int]] = None,
measurement_type: Optional[str] = None,
site_filepath: optionalPathType = None,
drop_duplicates: bool = True,
) -> Dict:
"""Read the datafile passed in and extract the data we require.
Args:
data_filepath: Path to file
site: Three letter site code
network: Network name
inlet: Inlet height
instrument: Instrument name
sampling_period: Sampling period in seconds
measurement_type: Measurement type e.g. insitu, flask
site_filepath: Alternative site info file (see openghg/supplementary_data repository for format).
Otherwise will use the data stored within openghg_defs/data/site_info JSON file by default.
drop_duplicates: Drop measurements at duplicate timestamps, keeping the first.
Returns:
dict: Dictionary of gas data
"""
import warnings
from openghg.util import clean_string, find_duplicate_timestamps, format_inlet, load_internal_json
from pandas import RangeIndex, read_csv, to_datetime
split_fname = data_filepath.stem.split(".")
site = site.lower()
try:
site_fname = clean_string(split_fname[0])
inlet_fname = clean_string(split_fname[3])
except IndexError:
raise ValueError(
"Error reading metadata from filename, we expect a form hfd.picarro.1minute.100m.dat"
)
if site_fname != site:
raise ValueError("Site mismatch between passed site code and that read from filename.")
if "m" not in inlet_fname:
raise ValueError("No inlet found, we expect filenames such as: bsd.picarro.1minute.108m.dat")
if inlet is not None and inlet != inlet_fname:
raise ValueError("Inlet mismatch between passed inlet and that read from filename.")
else:
inlet = inlet_fname
# Catch dtype warnings
# TODO - look at setting dtypes - read header and data separately?
with warnings.catch_warnings():
warnings.simplefilter("ignore")
data = read_csv(
data_filepath,
header=None,
skiprows=1,
sep=r"\s+",
parse_dates={"time": [0, 1]},
index_col="time",
)
dupes = find_duplicate_timestamps(data=data)
if dupes and not drop_duplicates:
raise ValueError(f"Duplicate dates detected: {dupes}")
data = data.loc[~data.index.duplicated(keep="first")]
# Get the number of gases in dataframe and number of columns of data present for each gas
n_gases, n_cols = _gas_info(data=data)
header = data.head(2)
skip_cols = sum([header[column][0] == "-" for column in header.columns])
metadata = _read_metadata(filepath=data_filepath, data=data)
if network is not None:
metadata["network"] = network
if sampling_period is not None:
sampling_period = float(sampling_period)
# Compare against value extracted from the file name
file_sampling_period = Timedelta(seconds=float(metadata["sampling_period"]))
given_sampling_period = Timedelta(seconds=sampling_period)
comparison_seconds = abs(given_sampling_period - file_sampling_period).total_seconds()
tolerance_seconds = 1
if comparison_seconds > tolerance_seconds:
raise ValueError(
f"Input sampling period {sampling_period} does not match to value "
f"extracted from the file name of {metadata['sampling_period']} seconds."
)
# Read the scale from JSON
# I'll leave this here for the possible future movement from class to functions
network_metadata = load_internal_json(filename="process_gcwerks_parameters.json")
crds_metadata = network_metadata["CRDS"]
# This dictionary is used to store the gas data and its associated metadata
combined_data = {}
for n in range(n_gases):
# Slice the columns
gas_data = data.iloc[:, skip_cols + n * n_cols : skip_cols + (n + 1) * n_cols]
# Reset the column numbers
gas_data.columns = RangeIndex(gas_data.columns.size)
species = gas_data[0][0]
species = species.lower()
column_labels = [
species,
f"{species}_variability",
f"{species}_number_of_observations",
]
# Name columns
gas_data = gas_data.set_axis(column_labels, axis="columns")
header_rows = 2
# Drop the first two rows now we have the name
gas_data = gas_data.drop(index=gas_data.head(header_rows).index)
gas_data.index = to_datetime(gas_data.index, format="%y%m%d %H%M%S")
# Cast data to float64 / double
gas_data = gas_data.astype("float64")
gas_data = gas_data.dropna(axis="rows", how="any")
# Here we can convert the Dataframe to a Dataset and then write the attributes
gas_data = gas_data.to_xarray()
site_attributes = _get_site_attributes(
site=site, inlet=inlet, crds_metadata=crds_metadata, site_filepath=site_filepath
)
scale = crds_metadata["default_scales"].get(species.upper(), "NA")
# Create a copy of the metadata dict
species_metadata = metadata.copy()
species_metadata["species"] = clean_string(species)
species_metadata["inlet"] = format_inlet(inlet, key_name="inlet")
species_metadata["calibration_scale"] = scale
species_metadata["long_name"] = site_attributes["long_name"]
species_metadata["data_type"] = "surface"
# Make sure metadata keys are included in attributes
site_attributes.update(species_metadata)
combined_data[species] = {
"metadata": species_metadata,
"data": gas_data,
"attributes": site_attributes,
}
return combined_data
def _read_metadata(filepath: Path, data: DataFrame) -> Dict:
"""Parse CRDS files and create a metadata dict
Args:
filepath: Data filepath
data: Raw pandas DataFrame
Returns:
dict: Dictionary containing metadata
"""
from openghg.util import format_inlet
# Find gas measured and port used
type_meas = data[2][2]
port = data[3][2]
# Split the filename to get the site and resolution
split_filename = str(filepath.name).split(".")
if len(split_filename) < 4:
raise ValueError(
"Error reading metadata from filename. The expected format is \
{site}.{instrument}.{sampling period}.{height}.dat"
)
site = split_filename[0]
instrument = split_filename[1]
sampling_period_str = split_filename[2]
inlet = split_filename[3]
if sampling_period_str == "1minute":
sampling_period = "60.0"
elif sampling_period_str == "hourly":
sampling_period = "3600.0"
else:
raise ValueError("Unable to read sampling period from filename.")
metadata = {}
metadata["site"] = site
metadata["instrument"] = instrument
metadata["sampling_period"] = str(sampling_period)
metadata["inlet"] = format_inlet(inlet, key_name="inlet")
metadata["port"] = port
metadata["type"] = type_meas
return metadata
def _get_site_attributes(
site: str,
inlet: str,
crds_metadata: Dict,
site_filepath: optionalPathType = None,
) -> Dict:
"""Gets the site specific attributes for writing to Datsets
Args:
site: Site name
inlet: Inlet height, example: 108m
crds_metadata: General CRDS metadata
site_filepath: Alternative site info file (see openghg/supplementary_data repository for format).
Otherwise will use the data stored within openghg_defs/data/site_info JSON file by default.
Returns:
dict: Dictionary of attributes
"""
from openghg.util import get_site_info, format_inlet
try:
site_attributes: Dict = crds_metadata["sites"][site.upper()]
global_attributes: Dict = site_attributes["global_attributes"]
except KeyError:
raise ValueError(f"Unable to read attributes for site: {site}")
# TODO - we need to combine the metadata
full_site_metadata = get_site_info(site_filepath)
attributes = global_attributes.copy()
try:
metadata = full_site_metadata[site.upper()]
except KeyError:
pass
else:
network_key = next(iter(metadata))
site_metadata = metadata[network_key]
attributes["station_latitude"] = str(site_metadata["latitude"])
attributes["station_longitude"] = str(site_metadata["longitude"])
attributes["station_long_name"] = site_metadata["long_name"]
attributes["station_height_masl"] = site_metadata["height_station_masl"]
attributes["inlet_height_magl"] = format_inlet(inlet, key_name="inlet_height_magl")
attributes["comment"] = crds_metadata["comment"]
attributes["long_name"] = site_attributes["gcwerks_site_name"]
return attributes
def _gas_info(data: DataFrame) -> Tuple[int, int]:
"""Returns the number of columns of data for each gas
that is present in the dataframe
Args:
data: Measurement data
Returns:
tuple (int, int): Number of gases, number of
columns of data for each gas
"""
from openghg.util import unanimous
# Slice the dataframe
head_row = data.head(1)
gases: Dict[str, int] = {}
# Loop over the gases and find each unique value
for column in head_row.columns:
s = head_row[column][0]
if s != "-":
gases[s] = gases.get(s, 0) + 1
# Check that we have the same number of columns for each gas
if not unanimous(gases):
raise ValueError(
"Each gas does not have the same number of columns. Please ensure data"
"is of the CRDS type expected by this module"
)
return len(gases), list(gases.values())[0]
