From https://groups.google.com/g/astropy-dev/c/m8pKTPvetF0
Heiko S.
We use astropy for user scripts in a telescope control system, otherwise erfa in the CS code. A change of Linux distribution brought us an upgrade of astropy from 5.3.3 to 7.01.
Our IERS data update strategy is to download IERS-A data regularly. So we aim for the highest precision. But if that fails (e.g. due to network access restrictions), and cached data is older than auto_max_age, then we would like to get only warnings logged by astropy.
This worked fine in the old version of astropy, with setting iers.conf.iers_degraded_accuracy = "warn", which yielded an IERSDegradedAccuracyWarning. It seems that with the inclusion of IERS-A data in astropy (commit 2da17a6 from #16187 that was follow-up for #14819), this config attribute is no longer applied to cached IERS-A data, but only to the IERS data that came already with the astropy installation. Instead of printing the warnings, astropy now fails with ValueError, which we don't want.
A possible workaround would be to set a very large auto_max_age, but then we don't even get the warnings that we actually like to see.
My question is, would it be possible to add a new config attribute that applies to cached IERS-A data, e.g. iers.conf.iers_degraded_accuracy_cached? Or to apply the existing attribute iers_degraded_accuracy to all IERS data sources (installation, previous download)? Or maybe I'm lacking imagination and one could get the old behavior back in a different way, without change in astropy?
Tim. Pickering
That data is now managed by the astropy-iers-data package. so to keep the data up to date, use pip to upgrade that package regularly. For our systems, I run a daily cron job to do that.
Marten van Kerkwijk
I think you are right that the different sources of IERS A data should be treated the same way, i.e., that the regression you are seeing should be considered a bug that we should fix.
(Indeed, if you are willing and able to write a PR that applies the existing iers_degraded_accuracy also to co-installed data, that would be very welcome!)
From https://groups.google.com/g/astropy-dev/c/m8pKTPvetF0
Heiko S.
We use astropy for user scripts in a telescope control system, otherwise erfa in the CS code. A change of Linux distribution brought us an upgrade of astropy from 5.3.3 to 7.01.
Our IERS data update strategy is to download IERS-A data regularly. So we aim for the highest precision. But if that fails (e.g. due to network access restrictions), and cached data is older than auto_max_age, then we would like to get only warnings logged by astropy.
This worked fine in the old version of astropy, with setting
iers.conf.iers_degraded_accuracy = "warn", which yielded an IERSDegradedAccuracyWarning. It seems that with the inclusion of IERS-A data in astropy (commit 2da17a6 from #16187 that was follow-up for #14819), this config attribute is no longer applied to cached IERS-A data, but only to the IERS data that came already with the astropy installation. Instead of printing the warnings, astropy now fails with ValueError, which we don't want.A possible workaround would be to set a very large auto_max_age, but then we don't even get the warnings that we actually like to see.
My question is, would it be possible to add a new config attribute that applies to cached IERS-A data, e.g.
iers.conf.iers_degraded_accuracy_cached? Or to apply the existing attribute iers_degraded_accuracy to all IERS data sources (installation, previous download)? Or maybe I'm lacking imagination and one could get the old behavior back in a different way, without change in astropy?Tim. Pickering
That data is now managed by the astropy-iers-data package. so to keep the data up to date, use pip to upgrade that package regularly. For our systems, I run a daily cron job to do that.
Marten van Kerkwijk
I think you are right that the different sources of IERS A data should be treated the same way, i.e., that the regression you are seeing should be considered a bug that we should fix.
(Indeed, if you are willing and able to write a PR that applies the existing
iers_degraded_accuracyalso to co-installed data, that would be very welcome!)