During the execution of the make_adb utility, the MODTRAN and FASCODE programs are executed as subprocesses. The inputs for these runs are created from the template tape5 file and the input simulation (.cfg) file. Once the specific MODTRAN or FASCODE run has completed, the make_adb utility parses the outputs and stores it into the atmospheric database.
The make_adb utility attempts to resolve any potential issues with the inputs that were supplied by the user before attempting to run the MODTRAN and FASCODE models. However, if either of these external models does not execute properly, or if the output of these models appears to be in error, one of the following messages will be printed to the screen:
make_adb: MODTRAN ERROR
MODTRAN appears to have crashed!
Reason is unknown and must be fixed manually!
Exiting ...
make_adb: FASCODE ERROR
FASCODE appears to have crashed!
Reason is unknown and must be fixed manually!
Exiting ...
In most cases, this arises from a problem in the MODTRAN template tape5 file. To find out specifically what error was encountered during the execution of the sub model, investigate the following sources:
Look at the appropriate log file for the external model that crashed. The name of these log files is defined in the make_adb configuration file and can be found by using the -config. These files are commonly named modtran.log and fascode.log. The contents of these files contain the messages that would normally be written to the screen if these programs were run stand-alone from the command line. Some error messages from MODTRAN and FASCODE will appear in this file.
For MODTRAN related errors, look at the tape6 output file generated by MODTRAN. The last lines in the file will most likely contain an explanation of why the run was aborted.
These sources of information are valuable when the problem is something that can be resolved by the user. These cases include problems with permissions, the model inputs, etc. In some rare cases, the problem is actually a bug with the make_adb utility itself, and a bug will have to submitted to the bug tracking system.
This error is issued when the user has configured a focal plane in the instrument that has a spectral resolution that exceeds the resolution limit for MODTRAN that is in the make_adb configuration file. The way to resolve this error is to either change the spectral resolution of your instrument focal plane or configure make_adb to use FASCODE.
Since FASCODE only runs on constant frequency/wavenumber centers, the make_adb utility cannot create a database for a simulation that contains a focal plane that exceeds the MODTRAN resolution limit and is defined in wavelength units.
This error message gets printed when the make_adb utility cannot create the temporary tape5 file in the directory that it is being run in. There are several reasons this may be the case:
The user running the make_adb utility does not have the appropriate file permissions to create a file in the current directory. In this case the directory might be owned by another user who has not enabled write permissions or the directory is owned by the current user but write permissions are not enabled.
There is already a read-only file in the current directory that is named tape5. In this case, the make_adb utility cannot overwrite this file since it lacks the write permission to do so.
There is directory in the current directory that is named tape5. In this case, the make_adb utility cannot create a file with the same name as an existing directory. The tape5 directory must be renamed in order for the make_adb utility to properly run.
This error message appears in modtran.log when make_adb is unable to execute MODTRAN.
Make sure that MODTRAN is properly installed. Also, ensure that the make_adb configuration file has the proper paths. Note that using the tilde (``~'') operator to specify a user home directory is not supported. A full system path must be supplied instead.
This error message will appear if the FASCODE executable specified in the make_adb config is invalid. This message will appear even if the spectral resolution of FASCODE is not needed for the ADB being generated. To correct the issue, either install and setup FASCODE correctly or omit the entire FASCODE section from the make_adb config file.