`max-ard` CLI¶

Grid Tools¶

Maxar ARD products are divided along a global discrete grid of 5km x 5km squares, organized by quadkeys and split into UTM zones.

The Python package maxar-canvas-grid offers functionality for working with ARD Grid cells and is covered in the SDK section. max-ard uses this package and installs it as a requirement

The CLI provides these tools for working with grid cells:

`max-ard cell describe`¶

Usage: max-ard cell describe CELL_ID [--format FORMAT] or max-ard cell describe QUADKEY ZONE [--format FORMAT]

Describes a zoom 12 grid cell as used by ARD tiles. Optionally, you can generate the cell as GeoJSON

Describe a grid cell with a full ID¶

A full cell ID starts has the following format:

z<two digit zone ID>-<quadkey>

This will return information about the cell:

% max-ard cell describe Z10-120002021202

Cell 120002021202 in zone 10
UTM bounds:
 Lower left corner: 540000.0, 4690000.0
 Upper right corner: 545000.0, 4695000.0
Geographic bounds:
 Lower left corner: -122.5142545446021, 42.36096845455453
 Upper right corner: -122.45314825564054, 42.40627045167697
Cell size: 0.0611062889615539m

Describe a grid cell with a quadkey and a zone¶

You can also run the command with just the quadkey followed by the zone number:

% max-ard cell describe 120002021202 10

Cell 120002021202 in zone 10
UTM bounds:
 Lower left corner: 540000.0, 4690000.0
 Upper right corner: 545000.0, 4695000.0
Geographic bounds:
 Lower left corner: -122.5142545446021, 42.36096845455453
 Upper right corner: -122.45314825564054, 42.40627045167697
Cell size: 0.0611062889615539m

Generate a GeoJSON representation of a cell¶

Use the --format geojson option to return GeoJSON:

% max-ard cell describe Z10-120002021202 --format geojson

{"type": "Feature", "properties": {"id": "Z10-120002021202"}, "geometry": {"type": "Polygon", "coordinates": [[[-122.45353889438631, 42.36096845455453], [-122.45314825564054, 42.405996718509776], [-122.51390730412858, 42.40627045167697], [-122.5142545446021, 42.36124175888317], [-122.45353889438631, 42.36096845455453]]]}}

Generate a GeoJSON file of a cell¶

Use output redirection with > <filename> and the previous example:

% max-ard cell describe Z08-03201333302  --format geojson > my_file.geojson

`max-ard cell covers`¶

Usage: max-ard cell covers GEOMETRY [--format FORMAT]

maxar-canvas-grid has a function called covers that calculates the grid cells covered by a given geometry.

The CLI offers a similar tool:

Find cell IDs covering a geometry¶

This tool can take WKT or GeoJSON strings as input geometries, and will output a list of all of the cell IDs that intersect the geometry.

% max-ard cell covers 'POINT( -122.5 42.4)'

Z10-120002021202

Generate GeoJSON of cells covering a geometry¶

The --format geojson option works the same as with max-ard cell describe and can generate GeoJSON of the cell(s) or send it to a file.

% max-ard cell covers 'POINT( -122.5 42.4)' --format geojson

{"type": "FeatureCollection", "features": [{"type": "Feature", "properties": {"id": "Z10-120002021202"}, "geometry": {"type": "Polygon", "coordinates": [[[-122.45353889438631, 42.36096845455453], [-122.45314825564054, 42.405996718509776], [-122.51390730412858, 42.40627045167697], [-122.5142545446021, 42.36124175888317], [-122.45353889438631, 42.36096845455453]]]}}]}

max-ard CLI¶