As discussed in #827, wis() didn't give a very informative error when there were no valid quantiles left. This PR changes quantile_to_interval_dataframe to throw an error when there are no valid intervals. This function is an internal function and I think you'd never want it to succeed if it wasn't able to produce a single valid forecast interval.
Checklist
[x] My PR is based on a package issue and I have explicitly linked it.
[x] I have included the target issue or issues in the PR title as follows: issue-number: PR title
[x] I have tested my changes locally.
[x] I have added or updated unit tests where necessary.
[x] I have updated the documentation if required.
[x] I have built the package locally and run rebuilt docs using roxygen2.
[x] My code follows the established coding standards and I have run lintr::lint_package() to check for style issues introduced by my changes.
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Description
This PR closes #827.
As discussed in #827,
wis()didn't give a very informative error when there were no valid quantiles left. This PR changesquantile_to_interval_dataframeto throw an error when there are no valid intervals. This function is an internal function and I think you'd never want it to succeed if it wasn't able to produce a single valid forecast interval.Checklist
lintr::lint_package()to check for style issues introduced by my changes.