Trying to read .nc (netCDF4) files in Azure Databricks.
Never worked with .nc files
/mnt/eco_dailyRain
"Can list the content of mount using dbutils.fs.ls("/mnt/eco_dailyRain")
OUTPUT:
Out[76]: [FileInfo(path='dbfs:/mnt/eco_dailyRain/2000.daily_rain.nc', name='2000.daily_rain.nc', size=429390127),
FileInfo(path='dbfs:/mnt/eco_dailyRain/2001.daily_rain.nc', name='2001.daily_rain.nc', size=428217143),
FileInfo(path='dbfs:/mnt/eco_dailyRain/2002.daily_rain.nc', name='2002.daily_rain.nc', size=428218181),
FileInfo(path='dbfs:/mnt/eco_dailyRain/2003.daily_rain.nc', name='2003.daily_rain.nc', size=428217139),
FileInfo(path='dbfs:/mnt/eco_dailyRain/2004.daily_rain.nc', name='2004.daily_rain.nc', size=429390143),
FileInfo(path='dbfs:/mnt/eco_dailyRain/2005.daily_rain.nc', name='2005.daily_rain.nc', size=428217137),
FileInfo(path='dbfs:/mnt/eco_dailyRain/2006.daily_rain.nc', name='2006.daily_rain.nc', size=428217127),
FileInfo(path='dbfs:/mnt/eco_dailyRain/2007.daily_rain.nc', name='2007.daily_rain.nc', size=428217143),
FileInfo(path='dbfs:/mnt/eco_dailyRain/2008.daily_rain.nc', name='2008.daily_rain.nc', size=429390137),
FileInfo(path='dbfs:/mnt/eco_dailyRain/2009.daily_rain.nc', name='2009.daily_rain.nc', size=428217127),
FileInfo(path='dbfs:/mnt/eco_dailyRain/2010.daily_rain.nc', name='2010.daily_rain.nc', size=428217134),
FileInfo(path='dbfs:/mnt/eco_dailyRain/2011.daily_rain.nc', name='2011.daily_rain.nc', size=428218181),
FileInfo(path='dbfs:/mnt/eco_dailyRain/2012.daily_rain.nc', name='2012.daily_rain.nc', size=429390127),
FileInfo(path='dbfs:/mnt/eco_dailyRain/2013.daily_rain.nc', name='2013.daily_rain.nc', size=428217143),
FileInfo(path='dbfs:/mnt/eco_dailyRain/2014.daily_rain.nc', name='2014.daily_rain.nc', size=428218104),
FileInfo(path='dbfs:/mnt/eco_dailyRain/2015.daily_rain.nc', name='2015.daily_rain.nc', size=428217134),
FileInfo(path='dbfs:/mnt/eco_dailyRain/2016.daily_rain.nc', name='2016.daily_rain.nc', size=429390127),
FileInfo(path='dbfs:/mnt/eco_dailyRain/2017.daily_rain.nc', name='2017.daily_rain.nc', size=428217223),
FileInfo(path='dbfs:/mnt/eco_dailyRain/2018.daily_rain.nc', name='2018.daily_rain.nc', size=418143765),
FileInfo(path='dbfs:/mnt/eco_dailyRain/2019.daily_rain.nc', name='2019.daily_rain.nc', size=370034113),
FileInfo(path='dbfs:/mnt/eco_dailyRain/Consignments.parquet', name='Consignments.parquet', size=237709917),
FileInfo(path='dbfs:/mnt/eco_dailyRain/test.nc', name='test.nc', size=428217137)]
Just to test wether can read from mount.
spark.read.parquet('dbfs:/mnt/eco_dailyRain/Consignments.parquet')
confirms can read parquet file.
output
Out[83]: DataFrame[CONSIGNMENT_PK: int, CERTIFICATE_NO: string, ACTOR_NAME: string, GENERATOR_FK: int, TRANSPORTER_FK: int, RECEIVER_FK: int, REC_POST_CODE: string, WASTEDESC: string, WASTE_FK: int, GEN_LICNUM: string, VOLUME: int, MEASURE: string, WASTE_TYPE: string, WASTE_ADD: string, CONTAMINENT1_FK: int, CONTAMINENT2_FK: int, CONTAMINENT3_FK: int, CONTAMINENT4_FK: int, TREATMENT_FK: int, ANZSICODE_FK: int, VEH1_REGNO: string, VEH1_LICNO: string, VEH2_REGNO: string, VEH2_LICNO: string, GEN_SIGNEE: string, GEN_DATE: timestamp, TRANS_SIGNEE: string, TRANS_DATE: timestamp, REC_SIGNEE: string, REC_DATE: timestamp, DATECREATED: timestamp, DISCREPANCY: string, APPROVAL_NUMBER: string, TR_TYPE: string, REC_WASTE_FK: int, REC_WASTE_TYPE: string, REC_VOLUME: int, REC_MEASURE: string, DATE_RECEIVED: timestamp, DATE_SCANNED: timestamp, HAS_IMAGE: string, LASTMODIFIED: timestamp]
But trying to read netCDF4
files says No such file or directory
Code:
import datetime as dt # Python standard library datetime module
import numpy as np
from netCDF4 import Dataset # http://code.google.com/p/netcdf4-python/
import matplotlib.pyplot as plt
rootgrp = Dataset("dbfs:/mnt/eco_dailyRain/2001.daily_rain.nc","r", format="NETCDF4")
Error
FileNotFoundError: [Errno 2] No such file or directory: b'dbfs:/mnt/eco_dailyRain/2001.daily_rain.nc'
Any clues.
According to the API reference of netCDF4 module
for class Dataset
, as the figure below.
The value of the path
parameter for Dataset
should be a path of unix directory format, but the path dbfs:/mnt/eco_dailyRain/2001.daily_rain.nc
is a format for PySpark as I known, so you got the error FileNotFoundError: [Errno 2] No such file or directory: b'dbfs:/mnt/eco_dailyRain/2001.daily_rain.nc'
.
The solution to fix it is to change the path value dbfs:/mnt/eco_dailyRain/2001.daily_rain.nc
with the equivalence unix path /dbfs/mnt/eco_dailyRain/2001.daily_rain.nc
, the code as below.
rootgrp = Dataset("/dbfs/mnt/eco_dailyRain/2001.daily_rain.nc","r", format="NETCDF4")
You can check it via the code below to see it.
%sh
ls /dbfs/mnt/eco_dailyRain
Ofcouse, you also can list your data files of netCDF4 format via dbutils.fs.ls('/mnt/eco_dailyRain')
if you had mount it.