Issue in converting `fastNLO` grids

[Radonirinaunimi]

Currently, there are some issues in converting certain fastNLO grids. For instance:

❯ pineappl import applfast-atlas-incjets-fnlo-arxiv-1410.8857-xsec001.tab.gz ATLAS_1JET_7TEV_R06_BIN2.pineappl.lz4 NNPDF40_nnlo_as_01180

which raises the following error:

thread 'main' (486912) panicked at pineappl_cli/src/import/fastnlo.rs:441:29:
assertion `left == right` failed
  left: 1
 right: 0

[Radonirinaunimi]

In hindsight, and after digging further, this might not actually be a bug. But, @cschwan, how does one know which functional form should one use for a scale?

[cschwan]

I don't remember why I wrote the assertion statement the way it is, but It's possible that I wrote the assertion statement in the transition time to version 1.0, when 4D arrays weren't working yet and I think #387 was the right thing to do. Why did you close it without merging?

Also note that the grid you've used above is included in the test-cli-import.sh script. I'm not sure why it was broken, did they change it on ploughshare? We should run this script periodically, but surely not which every commit. I'm not sure what the best strategy here is.

[Radonirinaunimi]

I see, I will resurrect the PR then and see what would be the best way to test this.

[cschwan]

Run ./test-cli-{export,import}.sh on the branch and tell me which grids fail; for the time being this should be enough.

[Radonirinaunimi]

Run ./test-cli-{export,import}.sh on the branch and tell me which grids fail; for the time being this should be enough.

With this change, everything works locally.

[cschwan]

In that case, merge it! 😄