wradlib.georef.rect.get_radolan_grid

wradlib.georef.rect.get_radolan_grid(nrows=None, ncols=None, **kwargs)

Calculates x/y coordinates of radolan grid of the German Weather Service

Returns the x,y coordinates of the radolan grid positions (lower left corner of every pixel). The radolan grid is a polarstereographic projection, the projection information was taken from RADOLAN-RADVOR-OP Kompositformat_2.2.2 [DWD, 2009]

Coordinates for 900km x 900km grid

Coordinate

lon

lat

x

y

LowerLeft

3.5889E

46.9526N

-523.4622

-4658.645

LowerRight

14.6209E

47.0705N

376.5378

-4658.645

UpperRight

15.7208E

54.7405N

376.5378

-3758.645

UpperLeft

2.0715E

54.5877N

-523.4622

-3758.645

Coordinates for 1100km x 900km grid

Coordinate

lon

lat

x

y

LowerLeft

4.6759E

46.1929N

-443.4622

-4758.645

LowerRight

15.4801E

46.1827N

456.5378

-4758.645

UpperRight

17.1128E

55.5342N

456.5378

-3658.645

UpperLeft

3.0889E

55.5482N

-443.4622

-3658.645

Coordinates for 1500km x 1400km grid

Coordinate

lon

lat

x

y

LowerLeft

2.3419E

43.9336N

-673.4622

-5008.645

Parameters:
  • nrows (int) – number of rows (460, 900 by default, 1100, 1500)

  • ncols (int) – number of columns (460, 900 by default, 1400)

Keyword Arguments:
  • wgs84 (bool) – if True, output coordinates are in wgs84 lonlat format (default: False)

  • mode (str) – ‘radolan’ - lower left pixel coordinates ‘center’ - pixel center coordinates ‘edge’ - pixel edge coordinates

  • proj (osgeo.osr.SpatialReference | str) – projection of the DWD grid with spheroid model or string trig to use trigonometric formulas for calculation (only for earth model - sphere). Defaults to None (earth model - sphere).

Returns:

radolan_grid (numpy.ndarray) – Array of xy- or lonlat-grid. shape is (nrows, ncols, 2) if mode=’radolan’ shape is (nrows, ncols, 2) if mode=’center’ shape is (nrows+1, ncols+1, 2) if mode=’edge’

Examples

>>> # using osr spatial reference transformation
>>> import wradlib.georef as georef  # noqa
>>> radolan_grid = georef.get_radolan_grid()
>>> print("{0}, ({1:.4f}, {2:.4f})".format(radolan_grid.shape, *radolan_grid[0,0,:]))  # noqa
(900, 900, 2), (-523.4622, -4658.6447)
>>> # using pure trigonometric transformations
>>> import wradlib.georef as georef
>>> radolan_grid = georef.get_radolan_grid(proj="trig")
>>> print("{0}, ({1:.4f}, {2:.4f})".format(radolan_grid.shape, *radolan_grid[0,0,:]))  # noqa
(900, 900, 2), (-523.4622, -4658.6447)
>>> # using osr spatial reference transformation
>>> import wradlib.georef as georef
>>> radolan_grid = georef.get_radolan_grid(1500, 1400)
>>> print("{0}, ({1:.4f}, {2:.4f})".format(radolan_grid.shape, *radolan_grid[0,0,:]))  # noqa
(1500, 1400, 2), (-673.4622, -5008.6447)
>>> # using osr spatial reference transformation
>>> import wradlib.georef as georef
>>> radolan_grid = georef.get_radolan_grid(900, 900, wgs84=True)
>>> print("{0}, ({1:.4f}, {2:.4f})".format(radolan_grid.shape, *radolan_grid[0,0,:]))  # noqa
(900, 900, 2), (3.5889, 46.9526)

See /notebooks/radolan/radolan_grid.ipynb#Polar-Stereographic-Projection.

Raises:

TypeError