"NameError: Netlist is empty" when using BSIM3 modelcards (and solution ?)

[cyber-g]

Environment (OS, Python version, PySpice version, simulator)

Debian GNU/Linux 10 (buster) Python 3.7.3 PySpice version : PySpice master on 20 March 2020 (version 1.3.2)

Problem statement and Actual Behaviour

I would like to use BSIM3 modelcards found in the archive : http://bsim.berkeley.edu/BSIM4/BSIM3/ftpv330.zip as "ftpv330/test/modelcard.nmos" and "ftpv330/test/modelcard.pmos"

When I put those files in the directory : PySpice/examples/libraries/transistor/ and rename as "*.mod" files, the example PySpice/examples/transistor/transistor.py fails to run :

python3 PySpice/examples/transistor/transistor.py
2020-03-20 - PySpice.Doc.ExampleTools.find_libraries - INFO - SPICE library path is /root/PySpice/examples/libraries
Traceback (most recent call last):
  File "PySpice/examples/transistor/transistor.py", line 30, in <module>
    spice_library = SpiceLibrary(libraries_path)
  File "/root/PySpice/PySpice/Spice/Library.py", line 76, in __init__
    spice_parser = SpiceParser(path)
  File "/root/PySpice/PySpice/Spice/Parser.py", line 805, in __init__
    self._statements = self._parse(lines)
  File "/root/PySpice/PySpice/Spice/Parser.py", line 846, in _parse
    raise NameError('Netlist is empty')
NameError: Netlist is empty

Expected Behaviour

The example should execute properly ; I just added some files in the library directory.

Steps to reproduce the behaviour

I have prepared a Docker file to reproduce the behaviour. Dockerfile.txt

Solution

The solution to the problem is given as comments in the end of the dockerfile.

In the Parser class, there is a test on the length of the netlist after formatting '+'-lines and removing comments. In my case, the netlist was only one single line. And it triggers the error NameError('Netlist is empty') .

That is why I propose to fix this issue by replacing the line if len(lines) <= 1: by : if len(lines) < 1:

Best regards

[cyber-g]

Dear Tom, Thanks for your reply ; your remark matches exactly the situation I have.

Looking again at the file example, the netlist has no title and begins directly with '.model ...'

I did not know the standard 1st line comment.

I will modify the netlist so that it is compliant.

It may be interesting to specify this element in the documentation.

How can I properly contribute ? In which file of the repository should I put this documentation element ?

(Sorry, I am beginning with this project and also beginner with python)

Best regards Germain

----- Mail original -----

De: "Tom Russo" notifications@github.com À: "FabriceSalvaire/PySpice" PySpice@noreply.github.com Cc: "cyber-g" cygerpham@free.fr, "Author" author@noreply.github.com Envoyé: Vendredi 20 Mars 2020 18:34:31 Objet: Re: [FabriceSalvaire/PySpice] "NameError: Netlist is empty" when using BSIM3 modelcards (and solution ?) (#189)

What I'm about to write may not be the problem you're describing, but it sounds like it might be. Standard SPICE netlist parsing considers the very first line of a netlist file as a comment (the title of the run). This has been true for as long as SPICE has existed. So if your top-level netlist file only has one line, the parser is correct to be ignoring that one line. If that's the issue, the correct solution is to add a title line to your netlist, not to modify the parser. — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub , or unsubscribe .

[cyber-g]

Looking more closely to the PySpice library code (SpiceParser._parse()), I have seen that models files must have a comment at the first line Best regards