problem in processing of MODIS L1A file to MODIS GEO file

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ivgbhavani
Posts: 16
Joined: Mon May 21, 2018 11:23 am America/New_York

problem in processing of MODIS L1A file to MODIS GEO file

by ivgbhavani » Wed May 23, 2018 8:47 am America/New_York

I wanted to generate MODIS L1B file using below mentioned L1A file(A2017358085500.L1A_LAC),
while processing from MODIS L1A file to MODIS GEO file,I am getting error. How can I solve this ?
can anyone help in this.

$ modis_GEO.py A2017358085500.L1A_LAC -v
Determining required attitude and ephemeris files...

Input file: A2017358085500.L1A_LAC
Sensor    : modisa
Start time: 2017358085500
End time  : 2017358085959

Cannot create geolocation from A2017358085500.L1A_LAC; exiting.
Error! could not establish a network connection. Check your network connection.
If you do not find a problem, please try again later.

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gfireman
Posts: 59
Joined: Thu Jan 07, 2010 2:59 pm America/New_York

problem in processing of MODIS L1A file to MODIS GEO file

by gfireman » Wed May 23, 2018 3:59 pm America/New_York

You need attitude and ephemeris files to generate a valid geolocation file.
If those are not specified, modis_GEO.py will call modis_atteph.py, which will try the following:
- look in a local database (defaults to $OCVARROOT/ancillary_data.db)
- query our database (for which you need a network connection)
The routine will then download the appropriate files, if not already present.

If your connection is shaky, just retry until it works.
Or you can schedule modis_atteph.py to query our database and download atteph files during times of known good connection.
In this case the call would be:
modis_atteph.py A2017358085500.L1A_LAC

ivgbhavani
Posts: 16
Joined: Mon May 21, 2018 11:23 am America/New_York

problem in processing of MODIS L1A file to MODIS GEO file

by ivgbhavani » Thu May 24, 2018 3:40 am America/New_York

Thank you for your reply..
I have given below command.. Than i got following
$modis_atteph.py A2017001083500.L1A_LAC -v
Aqua
Searching database: /home/bhavani/SEADAS74/ocssw/var/ancillary_data.db
Determining pass start and end times...
Aqua

Input file: A2017001083500.L1A_LAC
Sensor    : aqua
Start time: 2017001083500
End time  : 2017001083959

Error! could not establish a network connection. Check your network connection.
If you do not find a problem, please try again later.

zhigang
Posts: 69
Joined: Tue Nov 10, 2020 8:03 pm America/New_York

problem in processing of MODIS L1A file to MODIS GEO file

by zhigang » Thu May 24, 2018 9:10 am America/New_York

Dear Gwyn,

I also have this problem in modis_GEO.py. The details of error was:
root@vultr:~# modis_GEO.py A2018144055000.L1A_LAC
Traceback (most recent call last):
  File "/root/ocssw/scripts/modis_GEO.py", line 187, in <module>
    sys.exit(main())
  File "/root/ocssw/scripts/modis_GEO.py", line 173, in main
    modis_env(m)
  File "/root/ocssw/scripts/modules/modis_utils.py", line 264, in modis_env
    self.start, self.stop, self.sat_name = modis_timestamp(self.file)
  File "/root/ocssw/scripts/modules/modis_utils.py", line 151, in modis_timestamp
    sat_name = meta['ASSOCIATEDPLATFORMSHORTNAME'].lower()
TypeError: 'NoneType' object has no attribute '__getitem__'


My ocssw was v7.5, and I tried again after updateing ocssw, but it didn't work. Further, using the modis_atteph.py A2018144055000.L1A_LAC was also failed, the error was:
ERROR: For A2018143050500.L1A_LAC could not determine:  start time, start date, stoptime, stop date. Exiting.

What is the cause of this ?

Best Regards,
Zhigang

gfireman
Posts: 59
Joined: Thu Jan 07, 2010 2:59 pm America/New_York

problem in processing of MODIS L1A file to MODIS GEO file

by gfireman » Thu May 24, 2018 10:52 am America/New_York

Zhigang -

Try: ls -l A2018144055000.L1A_LAC; file A2018144055000.L1A_LAC

Mine looks like
-rw-rw-r-- 1 gfireman gfireman 571397213 2018-05-24 03:28 A2018144055000.L1A_LAC
A2018144055000.L1A_LAC: Hierarchical Data Format (version 4) data


If yours doesn't look like that, you might have to download again.

gfireman
Posts: 59
Joined: Thu Jan 07, 2010 2:59 pm America/New_York

problem in processing of MODIS L1A file to MODIS GEO file

by gfireman » Thu May 24, 2018 11:01 am America/New_York

Bhavani -

Do you have a network connection?

Try this from the command line:
curl https://oceandata.sci.gsfc.nasa.gov/Ancillary/?format=json

You should get:
{"rows":[["Aquarius\/","-","-"],["Attitude-Ephemeris\/","-","-"],["LUTs\/","-","-"],["OISST\/","-","-"],["Meteorological\/","-","-"]]}

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