Why not simply ask them for their code? It's a pain diving into someone else's code but it's doable.
I agree. That's the surest way to replicate their measurements.
Something to keep in mind is that GeoTol uses math that is quite different from legacy dimensions when positioning the DRF origin.
Legacy just uses the current alignment as the origin. If you align to the datums to report in legacy, it is using the math fit type that the features were measured with (typically a Least Squares Best fit).
GeoTol uses the datum features more like datum simulators, positioning the DRF origin at the high spots of the datums. Here is a link to a help file article that better explains this:
How PC-DMIS Solves and Uses Datums (hexagonmi.com)
So, you can use the exact same datums to report in GeoTol and Legacy and get different results. It is possible that your supplier used the same datums as the drawing calls out but chose to report in legacy because the different math gave them more favorable results. Not necessarily correct results.
Why not simply ask them for their code? It's a pain diving into someone else's code but it's doable.
I agree. That's the surest way to replicate their measurements.
Something to keep in mind is that GeoTol uses math that is quite different from legacy dimensions when positioning the DRF origin.
Legacy just uses the current alignment as the origin. If you align to the datums to report in legacy, it is using the math fit type that the features were measured with (typically a Least Squares Best fit).
GeoTol uses the datum features more like datum simulators, positioning the DRF origin at the high spots of the datums. Here is a link to a help file article that better explains this:
How PC-DMIS Solves and Uses Datums (hexagonmi.com)
So, you can use the exact same datums to report in GeoTol and Legacy and get different results. It is possible that your supplier used the same datums as the drawing calls out but chose to report in legacy because the different math gave them more favorable results. Not necessarily correct results.
My co-worker and I were discussing this today as we are headed from 2017 to 2022 or 2023. We pulled up a 2017 program in 2023, and edited a GDT callout. It was set at LSQ, perhaps a carryover from 2017, or perhaps a default settings setup.
What I'm saying is I believe if you measure your datum features using LSQ, you can keep that toggled to LSQ in Geotol and it won't use the default external fit type that they call 'constrained least squares'. I cannot stand that term, bc unless you are somewhat experienced you may think constrained least squares is a LSQ type fit when it is primarily an external fit as criteria #1 from my understanding. I"d prefer to call the new Geotol default 'External least squares' b/c that is what it is.
