When calculating an LCA "Cannot infer number of levels from empty list"

[joshmanley87]

Hello,

When I try to calculate a standard LCA the calculation stops and the following error message comes up:

File "C:\Users\c3071660\AppData\Local\anaconda3\envs\ab\Lib\site-packages\pandas\core\indexes\multi.py", line 609, in from_tuples
raise TypeError("Cannot infer number of levels from empty list")
TypeError: Cannot infer number of levels from empty list

It doesn't do this for other LCA setups so it must be something I have done to an activity, but I can't figure out what.

Can anyone help?
Thank you

[mrvisscher]

Hi @joshmanley87 !

Can you please share the full traceback of the error? That will be more helpful in trying to figure out what's going on exactly.

Kind regards,

Marin

[joshmanley87]

14:24:51 | ERROR | TypeError: Cannot infer number of levels from empty list
Traceback (most recent call last):
File "C:\Users\c3071660\AppData\Local\anaconda3\envs\ab\Lib\site-packages\activity_browser\layouts\tabs\LCA_results_tab.py", line 60, in generate_setup
new_tab = LCAResultsSubTab(data, self)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Users\c3071660\AppData\Local\anaconda3\envs\ab\Lib\site-packages\activity_browser\layouts\tabs\LCA_results_tabs.py", line 143, in init
ef=ElementaryFlowContributionTab(self),
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Users\c3071660\AppData\Local\anaconda3\envs\ab\Lib\site-packages\activity_browser\layouts\tabs\LCA_results_tabs.py", line 1196, in init
self.toggle_comparisons(self.switches.indexes.func)
File "C:\Users\c3071660\AppData\Local\anaconda3\envs\ab\Lib\site-packages\activity_browser\layouts\tabs\LCA_results_tabs.py", line 1058, in toggle_comparisons
self.update_tab()
File "C:\Users\c3071660\AppData\Local\anaconda3\envs\ab\Lib\site-packages\activity_browser\layouts\tabs\LCA_results_tabs.py", line 1131, in update_tab
self.set_combobox_changes()
File "C:\Users\c3071660\AppData\Local\anaconda3\envs\ab\Lib\site-packages\activity_browser\layouts\tabs\LCA_results_tabs.py", line 1117, in set_combobox_changes
self.df = self.update_dataframe(**compare_fields)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Users\c3071660\AppData\Local\anaconda3\envs\ab\Lib\site-packages\activity_browser\layouts\tabs\LCA_results_tabs.py", line 1206, in update_dataframe
return self.parent.contributions.top_elementary_flow_contributions(
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Users\c3071660\AppData\Local\anaconda3\envs\ab\Lib\site-packages\activity_browser\bwutils\multilca.py", line 864, in top_elementary_flow_contributions
labelled_df = self.get_labelled_contribution_dict(
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Users\c3071660\AppData\Local\anaconda3\envs\ab\Lib\site-packages\activity_browser\bwutils\multilca.py", line 627, in get_labelled_contribution_dict
joined = self.join_df_with_metadata(
^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Users\c3071660\AppData\Local\anaconda3\envs\ab\Lib\site-packages\activity_browser\bwutils\multilca.py", line 560, in join_df_with_metadata
df.index = pd.MultiIndex.from_tuples(ids_to_keys(df.index))
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Users\c3071660\AppData\Local\anaconda3\envs\ab\Lib\site-packages\pandas\core\indexes\multi.py", line 222, in new_meth
return meth(self_or_cls, *args, **kwargs)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Users\c3071660\AppData\Local\anaconda3\envs\ab\Lib\site-packages\pandas\core\indexes\multi.py", line 609, in from_tuples
raise TypeError("Cannot infer number of levels from empty list")
TypeError: Cannot infer number of levels from empty list

[mrvisscher]

Okay,

So what I think is happening is that one of your Impact Categories gives no result. Check whether your biosphere flows in your model match up with the impact categories that you're using.

Kind regards,

Marin

[joshmanley87]

Thank you for your quick reply Marin.

I have tried to strip back some of the LCA to figure out the problem. I have taken parts away leaving just ecoinvent 3.11 activities, and used only the CML GWP100 impact category. This still comes up with the same error as before. I have calculated similar products before and they have worked fine.

[mrvisscher]

What databases do you have in your project?

[joshmanley87]

Ecoinvent 3.11 cut off, biosphere3 and my own named capacitors.

…

________________________________ From: Marin Visscher ***@***.***> Sent: Friday, April 25, 2025 3:36:01 PM To: LCA-ActivityBrowser/activity-browser ***@***.***> Cc: joshmanley87 ***@***.***>; Mention ***@***.***> Subject: Re: [LCA-ActivityBrowser/activity-browser] When calculating an LCA "Cannot infer number of levels from empty list" (Discussion #1470) What databases do you have in your project? — Reply to this email directly, view it on GitHub<#1470 (reply in thread)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/BLLPJ5JZQ34VUZFWJO55WYD23JB5DAVCNFSM6AAAAAB33O7ISWVHI2DSMVQWIX3LMV43URDJONRXK43TNFXW4Q3PNVWWK3TUHMYTEOJUHAZDKNY>. You are receiving this because you were mentioned.Message ID: ***@***.***>

[mrvisscher]

And the other calculation setups are within the same project as well?

[joshmanley87]

Yes

…

________________________________ From: Marin Visscher ***@***.***> Sent: Friday, April 25, 2025 3:49:53 PM To: LCA-ActivityBrowser/activity-browser ***@***.***> Cc: joshmanley87 ***@***.***>; Mention ***@***.***> Subject: Re: [LCA-ActivityBrowser/activity-browser] When calculating an LCA "Cannot infer number of levels from empty list" (Discussion #1470) And the other calculation setups are within the same project as well? — Reply to this email directly, view it on GitHub<#1470 (reply in thread)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/BLLPJ5JYHTYH5GQVKHFUDND23JDRDAVCNFSM6AAAAAB33O7ISWVHI2DSMVQWIX3LMV43URDJONRXK43TNFXW4Q3PNVWWK3TUHMYTEOJUHAZTSMI>. You are receiving this because you were mentioned.Message ID: ***@***.***>

[mrvisscher]

Well in that case it's probably best if you send me an export of your project so I can take a closer look at it's internals. Feel free to send me one at m.r.visscher@cml.leidenuniv.nl