open TELEMAC-MASCARET The mathematically superior suite of solvers

Dear all

I'm trying to run a T3D simulation using v6p3.
It uses Spherical Coordinates (Lat and Lon as coordinate frame work). I have selected Spatial Projection Type: 3 (Lats and Lons which are converted to radians by applying calculation in corrxy). Geographic System 1 (WGS84 Lat/Lon).
I have specified a Latitude and Longitude of Origin Point.

As I understood the information in "future version v6p3" notes, this would convert my spherical coords to Mercator and I needed to provide coords in Lat/Lon (radians).

The model runs - but there is no output and no output mesh - so I assume the coordinate system information is wrong somewhere.

Have I mis-interpreted the notes? Do I still have to provide the conversion between Spherical Coords (Lat/Lon) to Mercator myself in Corrxy?
I would be grateful for a clarification of these settings and procedures to run a spherical coordinate model in v6p3.

Thanks
John

Hello,

I have put a correction on the trunk recently, that will be in version 6.3 R2 (due end of this month). Subroutine readgeo3 from library bief has to be corrected, this is where latitude-longitudes are converted to Mercator, and there the latitude and longitude of origin point need to be converted to radians as they are received in degrees (this is the mistake). If you cannot get it I can send it next Monday (our Linux network seems to be down currently). Another possibility is that you take the existing readgeo3 and consider that all latitudes and longitudes are in degrees (so you do nothing in corrxy if your original geometry file is in degrees). In readgeo3 you would have then to multiply all the latitudes and longitudes by PI/180, and it should do it.
Then the results file is given with Mercator projection.

I am not sure that asking for radians was a good idea, as everybody seems to have degrees, the more so because latitude and longitude of origin point is asked in degrees. Sorry for this.

With best regards,

Jean-Michel Hervouet

Ok - thanks Jean-Michel.

I will make those changes in readgeo3 and look forward to the new release.

John