Projections for Iowa South are now inaccurate

[jplhomer]

Sometime in the last 30 days (maybe longer), the projections being provided on SpatialReference.org for epsg:3418 (Iowa South) are inaccurate:

• Here's an example of a coordinate in EPSG:3418: 1623863.8131117225, 643763.90620113909
• The expected WGS84 is: lat: 41.766901, lng: -93.560676
• But today's result is: lat: 44.960581, lng: -79.222403

These calculations are performed using https://github.com/proj4php/proj4php which hasn't seen any changes short of changing the URL on spatialreference.org to use a .txt suffix.

I'm noticing the incorrect results on https://epsg.io/3418-1696 are incorrect, too (the map shows the new incorrect bounds, which are in Canada instead of Iowa where they used to be). Apologies if this means it's not isolated to this repository, but I'm not sure exactly where to report this.

Also wrote up some findings here: https://gis.stackexchange.com/questions/474573/projections-for-iowa-south-are-now-inaccurate-epsg-spatialreference

Thanks for your hard work on this project!

[rouault]

As far as I can see, both the information at https://spatialreference.org/ref/epsg/3418/prettywkt2.txt and https://spatialreference.org/ref/epsg/3418/proj4.txt is accurate, and in line with the official reference of https://epsg.org/crs/wkt/id/3418

epsg dot io is not a reference site, despite the misleading name.

This is something to check with the authors of https://github.com/proj4php/proj4php

[jplhomer]

Thanks @rouault - giving that a shot: https://github.com/proj4php/proj4php/issues/139

[jplhomer]

Update: it was indeed a Proj4PHP bug https://github.com/proj4php/proj4php/pull/140