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I'm trying to construct a DerivedCRS in OGC WKT form that describes a 3D local rectangular coordinate system that is sometimes referred to as an LSR or ENU or Topocentric. It has an origin described by a (lat,long,ht).

My best guess so far is this:

ENGCRS[
    "Topocentric example A",
    BASEGEODCRS[
        "WGS 84",
        DATUM[
            "WGS 84",
            ELLIPSOID["WGS 84",6378137,298.2572236,
                      LENGTHUNIT["metre",1.0]]
        ]
    ],
    DERIVINGCONVERSION[
        "Topocentric example A",
        METHOD[
            "Geographic/topocentric conversions",
            ID["EPSG",4326]
        ],
        PARAMETER["Latitude of topocentric origin",
                  55.0,ANGLEUNIT["degree",0.0174532925199433]],
        PARAMETER["Longitude of topocentric origin",
                  5.0,ANGLEUNIT["degree",0.0174532925199433]],
        PARAMETER["Ellipsoidal height of topocentric origin",
                  0.0,LENGTHUNIT["metre",1.0]]
    ],
    CS[Cartesian,3],
    AXIS["(X)",east,ORDER[1]],
    AXIS["(Y)",north,ORDER[2]],
    AXIS["(Zaq)",up,ORDER[3]],
    LENGTHUNIT["metre",1.0]
]

However, gdalsrsinfo -V says "Validate Fails - SRS is not well formed". I'm using gdalsrsinfo version 2.1.2 (2016-10-24).

I have a large number of points to convert, and will need to do this from time to time, so I would like to be able to construct the transform I need and feed it to a tool (like cs2cs) to batch convert a bunch of points at once.

How do I construct a CRS definition for the Topocentric coordinate system that I can use as input to a conversion tool, given the location for the origin of that coordinate system as a WGS-84 lat,lon,ht?

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