diff options
Diffstat (limited to 'docs/source/usage/operations/projections/rhealpix.rst')
| -rw-r--r-- | docs/source/usage/operations/projections/rhealpix.rst | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/docs/source/usage/operations/projections/rhealpix.rst b/docs/source/usage/operations/projections/rhealpix.rst new file mode 100644 index 00000000..5808cfaa --- /dev/null +++ b/docs/source/usage/operations/projections/rhealpix.rst @@ -0,0 +1,51 @@ +.. _rhealpix: + +******************************************************************************** +rHEALPix +******************************************************************************** ++---------------------+----------------------------------------------------------+ +| **Classification** | Mixed | ++---------------------+----------------------------------------------------------+ +| **Available forms** | Forward and inverse, spherical and elliptical projection | ++---------------------+----------------------------------------------------------+ +| **Defined area** | Global | ++---------------------+----------------------------------------------------------+ +| **Implemented by** | Alex Raichev and Michael Speth | ++---------------------+----------------------------------------------------------+ +| **Options** | ++---------------------+----------------------------------------------------------+ +| `+north_square` | Position of the north polar square. | +| | Valid inputs are 0--3. Defaults to 0. | ++---------------------+----------------------------------------------------------+ +| `+south_square` | Position of the south polar square. | +| | Valid inputs are 0--3. Defaults to 0. | ++---------------------+----------------------------------------------------------+ + +.. image:: ../../../../images/rhealpix.png + :scale: 75% + :alt: rHEALPix + +rHEALPix is a projection based on the HEALPix projection. The implementation of +rHEALPix uses the HEALPix projection. The rHEALPix combines the peaks of the +HEALPix into a square. The square's position can be translated and rotated across +the x-axis which is a noval approach for the rHEALPix projection. The initial +intention of using rHEALPix in the Spatial Computation Engine Science Collaboration +Environment (SCENZGrid). + +Usage +############################################################################### + +To run a rHEALPix projection on a WGS84 ellipsoidal model, use the following +command:: + + proj +proj=rhealpix -f '%.2f' +ellps=WGS84 +south_square=0 +north_square=2 -E << EOF + > 55 12 + > EOF + 55 12 6115727.86 1553840.13 + + +Further reading +################################################################################ + +#. `NASA <http://healpix.jpl.nasa.gov/>`_ +#. `Wikipedia <https://en.wikipedia.org/wiki/HEALPix>`_ |