[Proj] Unknown Datum

[Jean-Claude REPETTO]

On 11/26/10 13:09, Kassiane Mentz wrote:
> Hi.
> Thank you for your interest in help us in our problem.
> I'm send to you three test points:
>
> WGS84 (X Y Z)
>
> Point 1: 3462708,8379 -4304089,3245 -3178137,3434
> Point 2: 3463886,5098 -4304373,7494 -3176008,3278
> Point 3: 3460782,4780 -4304441,1369 -3179721,8848
>
> Local Datum (X Y Z)
>
> Point 1: 3462890,1150 -4304304,5191 -3178106,7914
> Point 2: 3464067,7475 -4304588,9297 -3175977,7717
> Point 3: 3460963,7766 -4304656,2961 -3179691,4114
>
> Ps: I remind you that we already have the conversion parameters (as you
> can see in my first email).

Hi,

These parameters :
+towgs84=-105.3687744788,128.2533004372,5.9501954062,-0.2526444267,4.9126506172,2.1177220547,-12.82833543
seem to give good results :

$ cs2cs +proj=geocent +towgs84=0,0,0,0,0,0,0 +to +proj=geocent 
+towgs84=-105.3687744788,128.2533004372,5.9501954062,-0.2526444267,4.9126506172,2.1177220547,-12.82833543
3462708.8379 -4304089.3245 -3178137.3434
3462890.13	-4304304.45 -3178106.86
3463886.5098 -4304373.7494 -3176008.3278
3464067.77	-4304588.90 -3175977.79
3460782.4780 -4304441.1369 -3179721.8848
3460963.78	-4304656.25 -3179691.47

Regards,
Jean-Claude