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diff --git a/docs/source/usage/operations/transformations/vgridshift.rst b/docs/source/usage/operations/transformations/vgridshift.rst deleted file mode 100644 index e9f78310..00000000 --- a/docs/source/usage/operations/transformations/vgridshift.rst +++ /dev/null @@ -1,41 +0,0 @@ -.. _vgridshift: - -================================================================================ -Vertical grid shift -================================================================================ - -Change Vertical datum change by grid shift - -+-----------------+--------------------------------------------------------------------+ -| **Input type** | Geodetic coordinates (horizontal), meters (vertical). | -+-----------------+--------------------------------------------------------------------+ -| **Output type** | Geodetic coordinates (horizontal), meters (vertical). | -+-----------------+--------------------------------------------------------------------+ -| **Options** | -+-----------------+--------------------------------------------------------------------+ -| `+grids` | Comma-separated list of grids to load. | -+-----------------+--------------------------------------------------------------------+ - -The vertical grid shift is done by offsetting the vertical input coordinates by -a specific amount determined by the loaded grids. The simplest use case of the -horizontal grid shift is applying a single grid. Here we change the vertical -reference from the ellipsoid to the global geoid model, EGM96:: - - +vgridshift +grids=egm96_16.gtx - - -More than one grid can be loaded at the same time, for instance in the case where -a better geoid model than the global is available for a certain area. Here the -gridshift is set up so that the local DVR90 geoid model takes presedence over -the global model:: - - +vgridshift +grids=@dvr90.gtx,egm96_16.gtx - -The ``@`` in the above example states that the grid is optional, in case the grid -is not found in the PROJ search path. The list of grids is prioritized so that -grids in the start of the list takes presedence over the grids in the back of the -list. - -PROJ supports the GTX file format for vertical grid corrections. Details -about all the format can be found in the GDAL documentation. GDAL both reads and -writes the format. Using GDAL for construction of new grids is recommended. |