Source code for pvlib.iotools.surfrad

Import functions for NOAA SURFRAD Data.
import io
from urllib.request import urlopen, Request
import pandas as pd
import numpy as np

    'year', 'jday', 'month', 'day', 'hour', 'minute', 'dt', 'zen',
    'dw_solar', 'dw_solar_flag', 'uw_solar', 'uw_solar_flag', 'direct_n',
    'direct_n_flag', 'diffuse', 'diffuse_flag', 'dw_ir', 'dw_ir_flag',
    'dw_casetemp', 'dw_casetemp_flag', 'dw_dometemp', 'dw_dometemp_flag',
    'uw_ir', 'uw_ir_flag', 'uw_casetemp', 'uw_casetemp_flag', 'uw_dometemp',
    'uw_dometemp_flag', 'uvb', 'uvb_flag', 'par', 'par_flag', 'netsolar',
    'netsolar_flag', 'netir', 'netir_flag', 'totalnet', 'totalnet_flag',
    'temp', 'temp_flag', 'rh', 'rh_flag', 'windspd', 'windspd_flag',
    'winddir', 'winddir_flag', 'pressure', 'pressure_flag']

# Dictionary mapping surfrad variables to pvlib names
    'zen': 'solar_zenith',
    'dw_solar': 'ghi',
    'dw_solar_flag': 'ghi_flag',
    'direct_n': 'dni',
    'direct_n_flag': 'dni_flag',
    'diffuse': 'dhi',
    'diffuse_flag': 'dhi_flag',
    'temp': 'temp_air',
    'temp_flag': 'temp_air_flag',
    'windspd': 'wind_speed',
    'windspd_flag': 'wind_speed_flag',
    'winddir': 'wind_direction',
    'winddir_flag': 'wind_direction_flag',
    'rh': 'relative_humidity',
    'rh_flag': 'relative_humidity_flag'

[docs]def read_surfrad(filename, map_variables=True): """Read in a daily NOAA SURFRAD file. The SURFRAD network is described in [1]_. Parameters ---------- filename: str Filepath or URL. URL can be either FTP or HTTP. map_variables: bool When true, renames columns of the Dataframe to pvlib variable names where applicable. See variable :const:`VARIABLE_MAP`. Returns ------- Tuple of the form (data, metadata). data: Dataframe Dataframe with the fields found below. metadata: dict Site metadata included in the file. Notes ----- Metadata dictionary includes the following fields: =============== ====== =============== Key Format Description =============== ====== =============== station String site name latitude Float site latitude longitude Float site longitude elevation Int site elevation surfrad_version Int surfrad version tz String Timezone (UTC) =============== ====== =============== Dataframe includes the following fields: ======================= ====== ========================================== raw, mapped Format Description ======================= ====== ========================================== **Mapped field names are returned when the map_variables argument is True** --------------------------------------------------------------------------- year int year as 4 digit int jday int day of year 1-365(or 366) month int month (1-12) day int day of month(1-31) hour int hour (0-23) minute int minute (0-59) dt float decimal time i.e. 23.5 = 2330 zen, solar_zenith float solar zenith angle (deg) **Fields below have associated qc flags labeled <field>_flag.** --------------------------------------------------------------------------- dw_solar, ghi float downwelling global solar(W/m^2) uw_solar float updownwelling global solar(W/m^2) direct_n, dni float direct normal solar (W/m^2) diffuse, dhi float downwelling diffuse solar (W/m^2) dw_ir float downwelling thermal infrared (W/m^2) dw_casetemp float downwelling IR case temp (K) dw_dometemp float downwelling IR dome temp (K) uw_ir float upwelling thermal infrared (W/m^2) uw_casetemp float upwelling IR case temp (K) uw_dometemp float upwelling IR case temp (K) uvb float global uvb (miliWatts/m^2) par float photosynthetically active radiation(W/m^2) netsolar float net solar (dw_solar - uw_solar) (W/m^2) netir float net infrared (dw_ir - uw_ir) (W/m^2) totalnet float net radiation (netsolar+netir) (W/m^2) temp, temp_air float 10-meter air temperature (?C) rh, relative_humidity float relative humidity (%) windspd, wind_speed float wind speed (m/s) winddir, wind_direction float wind direction (deg, clockwise from north) pressure float station pressure (mb) ======================= ====== ========================================== See README files located in the station directories in the SURFRAD data archives [2]_ for details on SURFRAD daily data files. In addition to the FTP server, the SURFRAD files are also available via HTTP access [3]_. References ---------- .. [1] NOAA Earth System Research Laboratory Surface Radiation Budget Network `SURFRAD Homepage <>`_ .. [2] NOAA SURFRAD Data Archive `SURFRAD Archive <>`_ .. [3] `NOAA SURFRAD HTTP Index <>`_ """ if str(filename).startswith('ftp') or str(filename).startswith('http'): req = Request(filename) response = urlopen(req) file_buffer = io.StringIO('ignore')) else: file_buffer = open(str(filename), 'r') # Read and parse the first two lines to build the metadata dict. station = file_buffer.readline() file_metadata = file_buffer.readline() metadata_list = file_metadata.split() metadata = {} metadata['name'] = station.strip() metadata['latitude'] = float(metadata_list[0]) metadata['longitude'] = float(metadata_list[1]) metadata['elevation'] = float(metadata_list[2]) metadata['surfrad_version'] = int(metadata_list[-1]) metadata['tz'] = 'UTC' data = pd.read_csv(file_buffer, delim_whitespace=True, header=None, names=SURFRAD_COLUMNS) file_buffer.close() data = format_index(data) missing = data == -9999.9 data = data.where(~missing, np.NaN) if map_variables: data.rename(columns=VARIABLE_MAP, inplace=True) return data, metadata
def format_index(data): """Create UTC localized DatetimeIndex for the dataframe. Parameters ---------- data: Dataframe Must contain columns 'year', 'jday', 'hour' and 'minute'. Return ------ data: Dataframe Dataframe with a DatetimeIndex localized to UTC. """ year = data.year.apply(str) jday = data.jday.apply(lambda x: '{:03d}'.format(x)) hours = data.hour.apply(lambda x: '{:02d}'.format(x)) minutes = data.minute.apply(lambda x: '{:02d}'.format(x)) index = pd.to_datetime(year + jday + hours + minutes, format="%Y%j%H%M") data.index = index data = data.tz_localize('UTC') return data