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Diffstat (limited to 'docs/source/usage/operations/transformations')
7 files changed, 126 insertions, 0 deletions
diff --git a/docs/source/usage/operations/transformations/cart.rst b/docs/source/usage/operations/transformations/cart.rst new file mode 100644 index 00000000..0c3c7c23 --- /dev/null +++ b/docs/source/usage/operations/transformations/cart.rst @@ -0,0 +1,24 @@ +.. _cart: + +================================================================================ +Cartesian to geodetic conversion +================================================================================ + +Convert geodetic coordinates to cartesian coordinates. + ++--------------+--------------------------------------------------------------------+ +| **Options** | ++--------------+--------------------------------------------------------------------+ +| `+ellps` | Ellipsoid of the input coordinates. If used together with the | +| | ellipsoid parameters below, ``+ellps`` is overwritten. | ++--------------+--------------------------------------------------------------------+ +| `+a` | Semi-major radius of ellipsoid axis. | ++--------------+--------------------------------------------------------------------+ +| `+b` | Semi-minor radius of ellipsoid axis. | ++--------------+--------------------------------------------------------------------+ +| `+es` | Eccentricity of ellipsoid. | ++--------------+--------------------------------------------------------------------+ +| `+f` | Flattening of ellipsoid. | ++--------------+--------------------------------------------------------------------+ + + diff --git a/docs/source/usage/operations/transformations/helmert.rst b/docs/source/usage/operations/transformations/helmert.rst new file mode 100644 index 00000000..46073b63 --- /dev/null +++ b/docs/source/usage/operations/transformations/helmert.rst @@ -0,0 +1,7 @@ +.. _helmert: + +================================================================================ +Helmert transform +================================================================================ + +Change reference frame by Helmert shift. diff --git a/docs/source/usage/operations/transformations/hgridshift.rst b/docs/source/usage/operations/transformations/hgridshift.rst new file mode 100644 index 00000000..78e46aa9 --- /dev/null +++ b/docs/source/usage/operations/transformations/hgridshift.rst @@ -0,0 +1,32 @@ +.. _hgridshift: + +================================================================================ +Horizontal grid shift +================================================================================ + +Change of horizontal datum by grid shift. + ++--------------+--------------------------------------------------------------------+ +| **Options** | ++--------------+--------------------------------------------------------------------+ +| `+grids` | Comma-separated list of grids to load. | ++--------------+--------------------------------------------------------------------+ + +The horizontal grid shift is done by offsetting the planar 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:: + + +hgridshift +grids=nzgr2kgrid0005.gsb + + +More than one grid can be loaded at the same time, for instance in case the +dataset needs to be transformed spans several countries. In this example grids +of the continental US, Alaska and Canada is loaded at the same time:: + + +hgridshift +grids=@conus,@alaska,@ntv2_0.gsb,@ntv_can.dat + +The ``@`` in the above example states that the grid is optional, in case the grid +is not found in the PROJ.4 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. + diff --git a/docs/source/usage/operations/transformations/index.rst b/docs/source/usage/operations/transformations/index.rst new file mode 100644 index 00000000..8bf2a890 --- /dev/null +++ b/docs/source/usage/operations/transformations/index.rst @@ -0,0 +1,15 @@ +.. _transformation_list: + +================================================================================ +Transformations +================================================================================ + +.. toctree:: + :maxdepth: 1 + + cart + helmert + molodensky + hgridshift + vgridshift + unitconvert diff --git a/docs/source/usage/operations/transformations/molodensky.rst b/docs/source/usage/operations/transformations/molodensky.rst new file mode 100644 index 00000000..3fa8f9a8 --- /dev/null +++ b/docs/source/usage/operations/transformations/molodensky.rst @@ -0,0 +1,7 @@ +.. _molodensky: + +================================================================================ +Molodensky transform +================================================================================ + +Perform a datum shift in geodetic coordinate space. diff --git a/docs/source/usage/operations/transformations/unitconvert.rst b/docs/source/usage/operations/transformations/unitconvert.rst new file mode 100644 index 00000000..458d0c15 --- /dev/null +++ b/docs/source/usage/operations/transformations/unitconvert.rst @@ -0,0 +1,7 @@ +.. _unitconvert: + +================================================================================ +Unit conversion +================================================================================ + +Convert between various distance and time units. diff --git a/docs/source/usage/operations/transformations/vgridshift.rst b/docs/source/usage/operations/transformations/vgridshift.rst new file mode 100644 index 00000000..f48d40c8 --- /dev/null +++ b/docs/source/usage/operations/transformations/vgridshift.rst @@ -0,0 +1,34 @@ +.. _vgridshift: + +================================================================================ +Vertical grid shift +================================================================================ + +Change Vertical datum change by grid shift + ++--------------+--------------------------------------------------------------------+ +| **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.4 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. + |