17 maidenhead

Working with Maidenhead in Vgrid DGGS¶

Full Vgrid DGGS documentation is available at vgrid document.

To work with Vgrid DGGS directly in GeoPandas and Pandas, please use vgridpandas. Full Vgridpandas DGGS documentation is available at vgridpandas document.

To work with Vgrid DGGS in QGIS, install the Vgrid Plugin.

To visualize DGGS in Maplibre GL JS, try the vgrid-maplibre library.

For an interactive demo, visit the Vgrid Homepage.

Install vgrid¶

Uncomment the following line to install vgrid.

In [1]:

# %pip install vgrid --upgrade

# %pip install vgrid --upgrade

latlon2maidenhead¶

In [2]:

from vgrid.conversion.latlon2dggs import latlon2maidenhead

lat = 10.775276
lon = 106.706797
res = 3
maidenhead_id = latlon2maidenhead(lat, lon, res)
maidenhead_id

from vgrid.conversion.latlon2dggs import latlon2maidenhead lat = 10.775276 lon = 106.706797 res = 3 maidenhead_id = latlon2maidenhead(lat, lon, res) maidenhead_id

Out[2]:

'OK30is'

Maidenhead to Polygon¶

In [3]:

from vgrid.conversion.dggs2geo.maidenhead2geo import maidenhead2geo

maidenhead_geo = maidenhead2geo(maidenhead_id)
maidenhead_geo

from vgrid.conversion.dggs2geo.maidenhead2geo import maidenhead2geo maidenhead_geo = maidenhead2geo(maidenhead_id) maidenhead_geo

Out[3]:

Maidenhead to GeoJSON¶

In [ ]:

from vgrid.conversion.dggs2geo.maidenhead2geo import maidenhead2geojson

maidenhead_geojson = maidenhead2geojson(maidenhead_id)
# maidenhead_geojson

from vgrid.conversion.dggs2geo.maidenhead2geo import maidenhead2geojson maidenhead_geojson = maidenhead2geojson(maidenhead_id) # maidenhead_geojson

Maidenhead Generator¶

In [5]:

from vgrid.generator.maidenheadgrid import maidenheadgrid

maidenhead_grid = maidenheadgrid(resolution=2, output_format="gpd")
# maidenhead_grid = maidenheadgrid(resolution=3,bbox=[102.14,7.69,114.86,23.39],output_format="gpd")
maidenhead_grid.plot(edgecolor="#3474eb", facecolor="none", linewidth=0.1)

from vgrid.generator.maidenheadgrid import maidenheadgrid maidenhead_grid = maidenheadgrid(resolution=2, output_format="gpd") # maidenhead_grid = maidenheadgrid(resolution=3,bbox=[102.14,7.69,114.86,23.39],output_format="gpd") maidenhead_grid.plot(edgecolor="#3474eb", facecolor="none", linewidth=0.1)

Generating Maidenhead DGGS:  93%|█████████▎| 30039/32400 [00:07<00:00, 2848.99 cells/s] 

Generating Maidenhead DGGS: 100%|██████████| 32400/32400 [00:09<00:00, 3506.94 cells/s]

Out[5]:

<Axes: >

Maidenhead Inspect¶

In [1]:

from vgrid.stats.maidenheadstats import maidenheadinspect

resolution = 2
maidenhead_inspect = maidenheadinspect(resolution)
maidenhead_inspect.head()

from vgrid.stats.maidenheadstats import maidenheadinspect resolution = 2 maidenhead_inspect = maidenheadinspect(resolution) maidenhead_inspect.head()

Generating Maidenhead DGGS: 100%|██████████| 32400/32400 [00:02<00:00, 14660.20 cells/s]

Out[1]:

	maidenhead	resolution	center_lat	center_lon	cell_width	cell_height	cell_area	cell_perimeter	geometry	crossed	norm_area	ipq	zsc	cvh
0	AA00	2	-89.5	-179.0	0.000000	111693.864914	2.176892e+08	227286.185413	POLYGON ((-180 -90, -178 -90, -178 -89, -180 -...	False	0.013828	0.052954	0.230118	1.0
1	AA01	2	-88.5	-179.0	3898.455585	111693.177216	6.529959e+08	235080.510047	POLYGON ((-180 -89, -178 -89, -178 -88, -180 -...	False	0.041479	0.148487	0.385339	1.0
2	AA02	2	-87.5	-179.0	7795.700029	111691.802680	1.088088e+09	242869.828017	POLYGON ((-180 -88, -178 -88, -178 -87, -180 -...	False	0.069117	0.231807	0.481463	1.0
3	AA03	2	-86.5	-179.0	11690.522628	111689.743022	1.522823e+09	250651.722215	POLYGON ((-180 -87, -178 -87, -178 -86, -180 -...	False	0.096732	0.304592	0.551897	1.0
4	AA04	2	-85.5	-179.0	15581.713544	111687.000814	1.957057e+09	258423.779413	POLYGON ((-180 -86, -178 -86, -178 -85, -180 -...	False	0.124315	0.368255	0.606839	1.0

Maidenhead Normalized Area Histogram¶

In [2]:

from vgrid.stats.maidenheadstats import maidenhead_norm_area_hist

maidenhead_norm_area_hist(maidenhead_inspect)

from vgrid.stats.maidenheadstats import maidenhead_norm_area_hist maidenhead_norm_area_hist(maidenhead_inspect)

Distribution of Maidenhead Area Distortions¶

In [3]:

from vgrid.stats.maidenheadstats import maidenhead_norm_area

maidenhead_norm_area(maidenhead_inspect)

from vgrid.stats.maidenheadstats import maidenhead_norm_area maidenhead_norm_area(maidenhead_inspect)

Maidenhead IPQ Compactness Histogram¶

Isoperimetric Inequality (IPQ) Compactness (suggested by Osserman, 1978):

$$C_{IPQ} = \frac{4 \pi A}{p^2}$$ The range of the IPQ compactness metric is [0,1].

A circle represents the maximum compactness with a value of 1.

As shapes become more irregular or elongated, their compactness decreases toward 0.

In [4]:

from vgrid.stats.maidenheadstats import maidenhead_compactness_ipq_hist

maidenhead_compactness_ipq_hist(maidenhead_inspect)

from vgrid.stats.maidenheadstats import maidenhead_compactness_ipq_hist maidenhead_compactness_ipq_hist(maidenhead_inspect)

Distribution of Maidenhead IPQ Compactness¶

In [7]:

from vgrid.stats.maidenheadstats import maidenhead_compactness_ipq

maidenhead_compactness_ipq(maidenhead_inspect)

from vgrid.stats.maidenheadstats import maidenhead_compactness_ipq maidenhead_compactness_ipq(maidenhead_inspect)

Maidenhead Convex hull Compactness Histogram:¶

$$C_{CVH} = \frac{A}{A_{CVH}}$$

The range of the convex hull compactness metric is [0,1].

As shapes become more concave, their convex hull compactness decreases toward 0.

In [8]:

from vgrid.stats.maidenheadstats import maidenhead_compactness_cvh_hist

maidenhead_compactness_cvh_hist(maidenhead_inspect)

from vgrid.stats.maidenheadstats import maidenhead_compactness_cvh_hist maidenhead_compactness_cvh_hist(maidenhead_inspect)

Distribution of Maidenhaed Convex hull Compactness¶

In [9]:

from vgrid.stats.maidenheadstats import maidenhead_compactness_cvh

maidenhead_compactness_cvh(maidenhead_inspect)

from vgrid.stats.maidenheadstats import maidenhead_compactness_cvh maidenhead_compactness_cvh(maidenhead_inspect)

Maidenhead Statistics¶

Characteristic Length Scale (CLS - suggested by Ralph Kahn): the diameter of a spherical cap of the same cell's area

In [2]:

from vgrid.stats import maidenheadstats

maidenheadstats("km")

from vgrid.stats import maidenheadstats maidenheadstats("km")

Out[2]:

	resolution	number_of_cells	avg_edge_len_km	avg_cell_area_km2	cls_km
0	1	324	1254.701801	1.574277e+06	1416.508668
1	2	32400	125.470180	1.574277e+04	141.578666
2	3	18662400	5.227924	2.733119e+01	5.899081
3	4	1866240000	0.522792	2.733119e-01	0.589908