Miscellaneous H3 functions - H3

import Tabs from '@theme/Tabs'; import TabItem from '@theme/TabItem';

These functions include descriptions of the H3 grid system.

degsToRads

Converts degrees to radians.

double degsToRads(double degrees);

</TabItem> <TabItem value="java">

:::note

Use java.lang.Math.toRadians(double degrees) instead.

:::

</TabItem> <TabItem value="javascript">

h3.degsToRads(degrees)

function example() {
  const degrees = 45;
  return h3.degsToRads(degrees);
}

</TabItem> <TabItem value="python">

:::note

Use math.radians(degrees) instead.

:::

</TabItem> <TabItem value="go">

degrees * h3.DegsToRads

</TabItem> <TabItem value="duckdb">

:::note

Use radians(degrees) instead.

:::

</TabItem> <TabItem value="shell">

$ h3 degsToRads --help
h3: Converts degrees to radians
H3 4.1.0

	degsToRads	Converts degrees to radians
	-d, --degree <DEG>	Required. Angle in degrees
	-h, --help	Show this help message.

bash

$ h3 degsToRads -d 180
3.1415926536

</TabItem> </Tabs>

radsToDegs

Converts radians to degrees.

double radsToDegs(double radians);

</TabItem> <TabItem value="java">

:::note

Use java.lang.Math.toDegrees(double radians) instead.

:::

</TabItem> <TabItem value="javascript">

h3.radsToDegs(h)

function example() {
  const radians = 3.14159;
  return h3.radsToDegs(radians);
}

</TabItem> <TabItem value="python">

:::note

Use math.degrees(radians) instead.

:::

</TabItem> <TabItem value="go">

radians * h3.RadsToDegs

</TabItem> <TabItem value="duckdb">

:::note

Use degrees(radians) instead.

:::

</TabItem> <TabItem value="shell">

$ h3 radsToDegs --help
h3: Converts radians to degrees
H3 4.1.0

	radsToDegs	Converts radians to degrees
	-r, --radian <RAD>	Required. Angle in radians
	-h, --help	Show this help message.

bash

$ h3 radsToDegs -r 1
57.2957795131

</TabItem> </Tabs>

getHexagonAreaAvgKm2

Average hexagon area in square kilometers at the given resolution. Excludes pentagons.

H3Error getHexagonAreaAvgKm2(int res, double *out);

</TabItem> <TabItem value="java">

java

double getHexagonAreaAvg(int res, AreaUnit unit);

</TabItem> <TabItem value="javascript">

h3.getHexagonAreaAvg(res, h3.UNITS.km2)

function example() {
  const res = 5;
  return h3.getHexagonAreaAvg(res, h3.UNITS.km2);
}

</TabItem> <TabItem value="python">

h3.average_hexagon_area(res, unit='km^2')

</TabItem> <TabItem value="go">

h3.HexagonAreaAvgKm2(res)

</TabItem> <TabItem value="duckdb">

sql

h3_average_hexagon_area(res, 'km^2')

</TabItem> <TabItem value="shell">

$ h3 getHexagonAreaAvgKm2 --help
h3: The average area in square kilometers for a hexagon of a given resolution (excludes pentagons)
H3 4.1.0

	getHexagonAreaAvgKm2	The average area in square kilometers for a hexagon of a given resolution (excludes pentagons)
	-r, --resolution <res>	Required. Resolution, 0-15 inclusive.
	-h, --help	Show this help message.

bash

$ h3 getHexagonAreaAvgKm2 -r 1
609788.4417941332

</TabItem> </Tabs>

getHexagonAreaAvgM2

Average hexagon area in square meters at the given resolution. Excludes pentagons.

H3Error getHexagonAreaAvgM2(int res, double *out);

</TabItem> <TabItem value="java">

java

double getHexagonAreaAvg(int res, AreaUnit unit);

</TabItem> <TabItem value="javascript">

h3.getHexagonAreaAvg(res, h3.UNITS.m2)

function example() {
  const res = 5;
  return h3.getHexagonAreaAvg(res, h3.UNITS.m2);
}

</TabItem> <TabItem value="python">

h3.average_hexagon_area(res, unit='m^2')

</TabItem> <TabItem value="go">

h3.HexagonAreaAvgM2(res)

</TabItem> <TabItem value="duckdb">

sql

h3_average_hexagon_area(res, 'm^2')

</TabItem> <TabItem value="shell">

$ h3 getHexagonAreaAvgM2 --help
h3: The average area in square meters for a hexagon of a given resolution (excludes pentagons)
H3 4.1.0

	getHexagonAreaAvgM2	The average area in square meters for a hexagon of a given resolution (excludes pentagons)
	-r, --resolution <res>	Required. Resolution, 0-15 inclusive.
	-h, --help	Show this help message.

bash

$ h3 getHexagonAreaAvgM2 -r 5
252903858.1819452047

</TabItem> </Tabs>

cellAreaRads2

Exact area of specific cell in square radians.

H3Error cellAreaRads2(H3Index h, double *out);

</TabItem> <TabItem value="java">

java

double cellArea(long h3, AreaUnit unit);
int cellArea(String h3Address, AreaUnit unit);

</TabItem> <TabItem value="javascript">

h3.cellArea(h, h3.UNITS.rads2)

function example() {
  const h = '85283473fffffff';
  return h3.cellArea(h, h3.UNITS.rads2);
}

</TabItem> <TabItem value="python">

h3.cell_area(h, unit='rads^2')

</TabItem> <TabItem value="go">

h3.CellAreaRads2(cell)

</TabItem> <TabItem value="duckdb">

sql

h3_cell_area(h, 'rads^2')

</TabItem> <TabItem value="shell">

$ h3 cellAreaRads2 --help
h3: The exact area of a specific cell in square radians
H3 4.1.0

	cellAreaRads2	The exact area of a specific cell in square radians
	-c, --cell <index>	Required. H3 Cell
	-h, --help	Show this help message.

bash

$ h3 cellAreaRads2 -c 85283473fffffff
0.0000065310

</TabItem> </Tabs>

cellAreaKm2

Exact area of specific cell in square kilometers.

H3Error cellAreaKm2(H3Index h, double *out);

</TabItem> <TabItem value="java">

java

double cellArea(long h3, AreaUnit unit);
int cellArea(String h3Address, AreaUnit unit);

</TabItem> <TabItem value="javascript">

h3.cellArea(h, h3.UNITS.km2)

function example() {
  const h = '85283473fffffff';
  return h3.cellArea(h, h3.UNITS.km2);
}

</TabItem> <TabItem value="python">

h3.cell_area(h, unit='km^2')

</TabItem> <TabItem value="go">

h3.CellAreaKm2(cell)

</TabItem> <TabItem value="duckdb">

sql

h3_cell_area(h, 'km^2')

</TabItem> <TabItem value="shell">

$ h3 cellAreaKm2 --help
h3: The exact area of a specific cell in square kilometers
H3 4.1.0

	cellAreaKm2	The exact area of a specific cell in square kilometers
	-c, --cell <index>	Required. H3 Cell
	-h, --help	Show this help message.

bash

$ h3 cellAreaKm2 -c 85283473fffffff
265.0925581283

</TabItem> </Tabs>

cellAreaM2

Exact area of specific cell in square meters.

H3Error cellAreaM2(H3Index h, double *out);

</TabItem> <TabItem value="java">

java

double cellArea(long h3, AreaUnit unit);
int cellArea(String h3Address, AreaUnit unit);

</TabItem> <TabItem value="javascript">

h3.cellArea(h, h3.UNITS.m2)

function example() {
  const h = '85283473fffffff';
  return h3.cellArea(h, h3.UNITS.m2);
}

</TabItem> <TabItem value="python">

h3.cell_area(h, unit='m^2')

</TabItem> <TabItem value="go">

h3.CellAreaM2(cell)

</TabItem> <TabItem value="duckdb">

sql

h3_cell_area(h, 'm^2')

</TabItem> <TabItem value="shell">

$ h3 cellAreaM2 --help
h3: The exact area of a specific cell in square meters
H3 4.1.0

	cellAreaM2	The exact area of a specific cell in square meters
	-c, --cell <index>	Required. H3 Cell
	-h, --help	Show this help message.

bash

$ h3 cellAreaM2 -c 85283473fffffff
265092558.1282823086

</TabItem> </Tabs>

getHexagonEdgeLengthAvgKm

Average hexagon edge length in kilometers at the given resolution. Excludes pentagons.

H3Error getHexagonEdgeLengthAvgKm(int res, double *out);

</TabItem> <TabItem value="java">

java

double getHexagonEdgeLengthAvg(int res, LengthUnit unit);

</TabItem> <TabItem value="javascript">

h3.getHexagonEdgeLengthAvg(res, h3.UNITS.km)

function example() {
  const res = 5;
  return h3.getHexagonEdgeLengthAvg(res, h3.UNITS.km);
}

</TabItem> <TabItem value="python">

h3.average_hexagon_edge_length(res, unit='km')

</TabItem> <TabItem value="go">

h3.HexagonEdgeLengthAvgKm(res)

</TabItem> <TabItem value="duckdb">

sql

h3_average_hexagon_edge_length(res, 'km')

</TabItem> <TabItem value="shell">

$ h3 getHexagonEdgeLengthAvgKm --help
h3: The average hexagon edge length in kilometers of a given resolution (excludes pentagons)
H3 4.1.0

	getHexagonEdgeLengthAvgKm	The average hexagon edge length in kilometers of a given resolution (excludes pentagons)
	-r, --resolution <res>	Required. Resolution, 0-15 inclusive.
	-h, --help	Show this help message.

bash

$ h3 getHexagonEdgeLengthAvgKm -r 5
9.8540909900

</TabItem> </Tabs>

getHexagonEdgeLengthAvgM

Average hexagon edge length in meters at the given resolution. Excludes pentagons.

H3Error getHexagonEdgeLengthAvgM(int res, double *out);

</TabItem> <TabItem value="java">

java

double getHexagonEdgeLengthAvg(int res, LengthUnit unit);

</TabItem> <TabItem value="javascript">

h3.getHexagonEdgeLengthAvg(res, h3.UNITS.m)

function example() {
  const res = 5;
  return h3.getHexagonEdgeLengthAvg(res, h3.UNITS.m);
}

</TabItem> <TabItem value="python">

h3.average_hexagon_edge_length(res, unit='m')

</TabItem> <TabItem value="go">

h3.HexagonEdgeLengthAvgM(res)

</TabItem> <TabItem value="duckdb">

sql

h3_average_hexagon_edge_length(res, 'm')

</TabItem> <TabItem value="shell">

$ h3 getHexagonEdgeLengthAvgM --help
h3: The average hexagon edge length in meters of a given resolution (excludes pentagons)
H3 4.1.0

	getHexagonEdgeLengthAvgM	The average hexagon edge length in meters of a given resolution (excludes pentagons)
	-r, --resolution <res>	Required. Resolution, 0-15 inclusive.
	-h, --help	Show this help message.

bash

$ h3 getHexagonEdgeLengthAvgM -r 5
9854.0909900000

</TabItem> </Tabs>

edgeLengthKm

Exact edge length of specific unidirectional edge in kilometers.

H3Error edgeLengthKm(H3Index edge, double *length);

</TabItem> <TabItem value="java">

java

double edgeLength(long h3, LengthUnit unit);
double edgeLength(String h3Address, LengthUnit unit);

</TabItem> <TabItem value="javascript">

h3.edgeLength(h3, h3.UNITS.km)

function example() {
  const h = '115283473fffffff';
  return h3.edgeLength(h, h3.UNITS.km);
}

</TabItem> <TabItem value="python">

h3.edge_length(h, unit='km')

</TabItem> <TabItem value="go">

h3.EdgeLengthKm(edge)

</TabItem> <TabItem value="duckdb">

sql

h3_edge_length(h, 'km')

</TabItem> <TabItem value="shell">

$ h3 edgeLengthKm --help
h3: The exact edge length of a specific directed edge in kilometers
H3 4.1.0

	edgeLengthKm	The exact edge length of a specific directed edge in kilometers
	-c, --cell <index>	Required. H3 Cell
	-h, --help	Show this help message.

bash

$ h3 edgeLengthKm -c 115283473fffffff
10.2947360862

</TabItem> </Tabs>

edgeLengthM

Exact edge length of specific unidirectional edge in meters.

H3Error edgeLengthM(H3Index edge, double *length);

</TabItem> <TabItem value="java">

java

double edgeLength(long h3, LengthUnit unit);
double edgeLength(String h3Address, LengthUnit unit);

</TabItem> <TabItem value="javascript">

h3.edgeLength(h3, h3.UNITS.m)

function example() {
  const h = '115283473fffffff';
  return h3.edgeLength(h, h3.UNITS.m);
}

</TabItem> <TabItem value="python">

h3.edge_length(h, unit='m')

</TabItem> <TabItem value="go">

h3.EdgeLengthM(edge)

</TabItem> <TabItem value="duckdb">

sql

h3_edge_length(h, 'm')

</TabItem> <TabItem value="shell">

$ h3 edgeLengthM --help
h3: The exact edge length of a specific directed edge in meters
H3 4.1.0

	edgeLengthM	The exact edge length of a specific directed edge in meters
	-c, --cell <index>	Required. H3 Cell
	-h, --help	Show this help message.

bash

$ h3 edgeLengthM -c 115283473fffffff
10294.7360861995

</TabItem> </Tabs>

edgeLengthRads

Exact edge length of specific unidirectional edge in radians.

H3Error edgeLengthRads(H3Index edge, double *length);

</TabItem> <TabItem value="java">

java

double edgeLength(long h3, LengthUnit unit);
double edgeLength(String h3Address, LengthUnit unit);

</TabItem> <TabItem value="javascript">

h3.edgeLength(h3, h3.UNITS.rads)

function example() {
  const h = '115283473fffffff';
  return h3.edgeLength(h, h3.UNITS.rads);
}

</TabItem> <TabItem value="python">

h3.edge_length(h, unit='rads')

</TabItem> <TabItem value="go">

h3.EdgeLengthRads(edge)

</TabItem> <TabItem value="duckdb">

sql

h3_edge_length(h, 'rads')

</TabItem> <TabItem value="shell">

$ h3 edgeLengthRads --help
h3: The exact edge length of a specific directed edge in radians
H3 4.1.0

	edgeLengthRads	The exact edge length of a specific directed edge in radians
	-c, --cell <index>	Required. H3 Cell
	-h, --help	Show this help message.

bash

$ h3 edgeLengthRads -c 115283473fffffff
0.0016158726

</TabItem> </Tabs>

getNumCells

Number of unique H3 indexes at the given resolution.

H3Error getNumCells(int res, int64_t *out);

</TabItem> <TabItem value="java">

java

long getNumCells(int res);

</TabItem> <TabItem value="javascript">

h3.getNumCells(res)

function example() {
  const res = 5;
  return h3.getNumCells(res);
}

</TabItem> <TabItem value="python">

h3.get_num_cells(res)

</TabItem> <TabItem value="go">

h3.NumCells(res)

</TabItem> <TabItem value="duckdb">

sql

h3_get_num_cells(res)

</TabItem> <TabItem value="shell">

$ h3 getNumCells --help
h3: The number of unique H3 cells for a specified resolution
H3 4.1.0

	getNumCells	The number of unique H3 cells for a specified resolution
	-r, --resolution <res>	Required. Resolution, 0-15 inclusive.
	-h, --help	Show this help message.

bash

$ h3 getNumCells -r 5
2016842

</TabItem> </Tabs>

getRes0Cells

Provide all the resolution 0 H3 cells. These are the coarsest cells that can be represented in the H3 system and are the parents/ancestors of all other cells in the H3 grid system. The returned cells correspond to the 122 base cells.

H3Error getRes0Cells(H3Index *out);

out must be an array of at least size res0CellCount().

</TabItem> <TabItem value="java">

java

Collection<Long> getRes0Cells();
Collection<String> getRes0CellAddresses();

</TabItem> <TabItem value="javascript">

h3.getRes0Cells()

function example() {
  return h3.getRes0Cells();
}

</TabItem> <TabItem value="python">

h3.get_res0_cells()

</TabItem> <TabItem value="go">

h3.Res0Cells()

</TabItem> <TabItem value="duckdb">

sql

h3_get_res0_cells()

sql

h3_get_res0_cells_string()

</TabItem> <TabItem value="shell">

$ h3 getRes0Cells --help
h3: Returns all of the resolution 0 cells
H3 4.1.0

	getRes0Cells	Returns all of the resolution 0 cells
	-h, --help	Show this help message.
	-f, --format <FMT>	'json' for ["CELL", ...], 'newline' for CELL\n... (Default: json)

bash

$ h3 getRes0Cells
[ "8001fffffffffff", "8003fffffffffff", "8005fffffffffff", "8007fffffffffff", "8009fffffffffff", "800bfffffffffff", "800dfffffffffff", "800ffffffffffff", "8011fffffffffff", "8013fffffffffff", "8015fffffffffff", "8017fffffffffff", "8019fffffffffff", "801bfffffffffff", "801dfffffffffff", "801ffffffffffff", "8021fffffffffff", "8023fffffffffff", "8025fffffffffff", "8027fffffffffff", "8029fffffffffff", "802bfffffffffff", "802dfffffffffff", "802ffffffffffff", "8031fffffffffff", "8033fffffffffff", "8035fffffffffff", "8037fffffffffff", "8039fffffffffff", "803bfffffffffff", "803dfffffffffff", "803ffffffffffff", "8041fffffffffff", "8043fffffffffff", "8045fffffffffff", "8047fffffffffff", "8049fffffffffff", "804bfffffffffff", "804dfffffffffff", "804ffffffffffff", "8051fffffffffff", "8053fffffffffff", "8055fffffffffff", "8057fffffffffff", "8059fffffffffff", "805bfffffffffff", "805dfffffffffff", "805ffffffffffff", "8061fffffffffff", "8063fffffffffff", "8065fffffffffff", "8067fffffffffff", "8069fffffffffff", "806bfffffffffff", "806dfffffffffff", "806ffffffffffff", "8071fffffffffff", "8073fffffffffff", "8075fffffffffff", "8077fffffffffff", "8079fffffffffff", "807bfffffffffff", "807dfffffffffff", "807ffffffffffff", "8081fffffffffff", "8083fffffffffff", "8085fffffffffff", "8087fffffffffff", "8089fffffffffff", "808bfffffffffff", "808dfffffffffff", "808ffffffffffff", "8091fffffffffff", "8093fffffffffff", "8095fffffffffff", "8097fffffffffff", "8099fffffffffff", "809bfffffffffff", "809dfffffffffff", "809ffffffffffff", "80a1fffffffffff", "80a3fffffffffff", "80a5fffffffffff", "80a7fffffffffff", "80a9fffffffffff", "80abfffffffffff", "80adfffffffffff", "80affffffffffff", "80b1fffffffffff", "80b3fffffffffff", "80b5fffffffffff", "80b7fffffffffff", "80b9fffffffffff", "80bbfffffffffff", "80bdfffffffffff", "80bffffffffffff", "80c1fffffffffff", "80c3fffffffffff", "80c5fffffffffff", "80c7fffffffffff", "80c9fffffffffff", "80cbfffffffffff", "80cdfffffffffff", "80cffffffffffff", "80d1fffffffffff", "80d3fffffffffff", "80d5fffffffffff", "80d7fffffffffff", "80d9fffffffffff", "80dbfffffffffff", "80ddfffffffffff", "80dffffffffffff", "80e1fffffffffff", "80e3fffffffffff", "80e5fffffffffff", "80e7fffffffffff", "80e9fffffffffff", "80ebfffffffffff", "80edfffffffffff", "80effffffffffff", "80f1fffffffffff", "80f3fffffffffff" ]

</TabItem> </Tabs>

res0CellCount

Number of resolution 0 H3 indexes, which is defined as 122.

int res0CellCount(void);

</TabItem> <TabItem value="java">

:::note

This function exists for memory management and is not exposed.

:::

</TabItem> <TabItem value="javascript">

:::note

This function exists for memory management and is not exposed.

:::

</TabItem> <TabItem value="python">

:::note

This function exists for memory management and is not exposed.

:::

</TabItem> <TabItem value="go">

:::note

This function exists for memory management and is not exposed.

:::

</TabItem> <TabItem value="duckdb">

:::note

This function exists for memory management and is not exposed.

:::

</TabItem> <TabItem value="shell">

:::note

This function exists for memory management and is not exposed.

:::

</TabItem> </Tabs>

getPentagons

All the pentagon H3 cells at the specified resolution. There are 12 pentagons at each resolution.

H3Error getPentagons(int res, H3Index *out);

out must be an array of at least size pentagonIndexCount().

Returns 0 (E_SUCCESS) on success.

</TabItem> <TabItem value="java">

java

Collection<Long> h3.getPentagons(int res);
Collection<String> h3.getPentagonsAddresses(int res);

</TabItem> <TabItem value="javascript">

h3.getPentagons(res)

function example() {
  const res = 5;
  return h3.getPentagons(res);
}

</TabItem> <TabItem value="python">

h3.get_pentagons(res)

</TabItem> <TabItem value="go">

h3.Pentagons(res)

</TabItem> <TabItem value="duckdb">

sql

h3_get_pentagons(res)

sql

h3_get_pentagons_string(res)

</TabItem> <TabItem value="shell">

$ h3 getPentagons --help
h3: Returns all of the pentagons at the specified resolution
H3 4.1.0

	getPentagons	Returns all of the pentagons at the specified resolution
	-r, --resolution <res>	Required. Resolution, 0-15 inclusive.
	-h, --help	Show this help message.
	-f, --format <FMT>	'json' for ["CELL", ...], 'newline' for CELL\n... (Default: json)

bash

$ h3 getPentagons -r 5
[ "85080003fffffff", "851c0003fffffff", "85300003fffffff", "854c0003fffffff", "85620003fffffff", "85740003fffffff", "857e0003fffffff", "85900003fffffff", "85a60003fffffff", "85c20003fffffff", "85d60003fffffff", "85ea0003fffffff" ]

</TabItem> </Tabs>

pentagonCount

Number of pentagon H3 cells per resolution. This is always 12, but provided as a convenience.

int pentagonCount(void);

</TabItem> <TabItem value="java">

:::note

This function exists for memory management and is not exposed.

:::

</TabItem> <TabItem value="javascript">

:::note

This function exists for memory management and is not exposed.

:::

</TabItem> <TabItem value="python">

:::note

This function exists for memory management and is not exposed.

:::

</TabItem> <TabItem value="go">

h3.NumPentagons

</TabItem> <TabItem value="duckdb">

:::note

This function exists for memory management and is not exposed.

:::

</TabItem> <TabItem value="shell">

$ h3 pentagonCount --help
h3: Returns 12
H3 4.1.0

	pentagonCount	Returns 12
	-h, --help	Show this help message.

bash

$ h3 pentagonCount
12

</TabItem> </Tabs>

greatCircleDistanceKm

Gives the "great circle" or "haversine" distance between pairs of LatLng points (lat/lng pairs) in kilometers.

double greatCircleDistanceKm(const LatLng *a, const LatLng *b);

</TabItem> <TabItem value="java">

java

double greatCircleDistance(LatLng point1, LatLng point2, LengthUnit unit);

</TabItem> <TabItem value="javascript">

h3.greatCircleDistance(point1, point2, h3.UNITS.km)

function example() {
  const point1 = [-10, 0];
  const point2 = [10, 0];
  return h3.greatCircleDistance(point1, point2, h3.UNITS.km)
}

</TabItem> <TabItem value="python">

h3.great_circle_distance(point1, point2, unit='km')

</TabItem> <TabItem value="go">

h3.GreatCircleDistanceKm(h3.NewLatLng(latA, lngA), h3.NewLatLng(latB, lngB))

</TabItem> <TabItem value="duckdb">

sql

h3_great_circle_distance(point1, point2, 'km')

</TabItem> <TabItem value="shell">

$ h3 greatCircleDistanceKm --help
h3: Calculates the 'great circle' or 'haversine' distance between two lat, lng points, in kilometers
H3 4.1.0

	greatCircleDistanceKm	Calculates the 'great circle' or 'haversine' distance between two lat, lng points, in kilometers
	-i, --file <FILENAME>	The file to load the coordinates from. Use -- to read from stdin.
	-c, --coordinates <ARRAY>	The array of coordinates to convert. Up to 1500 characters.
	-h, --help	Show this help message.

bash

$ h3 greatCircleDistanceKm -c "[[-10, 0], [10, 0]]"
2223.9010395046

</TabItem> </Tabs>

greatCircleDistanceM

Gives the "great circle" or "haversine" distance between pairs of LatLng points (lat/lng pairs) in meters.

double greatCircleDistanceM(const LatLng *a, const LatLng *b);

</TabItem> <TabItem value="java">

java

double greatCircleDistance(LatLng point1, LatLng point2, LengthUnit unit);

</TabItem> <TabItem value="javascript">

h3.greatCircleDistance(point1, point2, h3.UNITS.m);

function example() {
  const point1 = [-10, 0];
  const point2 = [10, 0];
  return h3.greatCircleDistance(point1, point2, h3.UNITS.m);
}

</TabItem> <TabItem value="python">

h3.great_circle_distance(point1, point2, unit='m')

</TabItem> <TabItem value="go">

h3.GreatCircleDistanceM(h3.NewLatLng(latA, lngA), h3.NewLatLng(latB, lngB))

</TabItem> <TabItem value="duckdb">

sql

h3_great_circle_distance(point1, point2, 'm')

</TabItem> <TabItem value="shell">

$ h3 greatCircleDistanceM --help
h3: Calculates the 'great circle' or 'haversine' distance between two lat, lng points, in meters
H3 4.1.0

	greatCircleDistanceM	Calculates the 'great circle' or 'haversine' distance between two lat, lng points, in meters
	-i, --file <FILENAME>	The file to load the coordinates from. Use -- to read from stdin.
	-c, --coordinates <ARRAY>	The array of coordinates to convert. Up to 1500 characters.
	-h, --help	Show this help message.

bash

$ h3 greatCircleDistanceM -c "[[-10, 0], [10, 0]]"
2223901.0395045886

</TabItem> </Tabs>

greatCircleDistanceRads

Gives the "great circle" or "haversine" distance between pairs of LatLng points (lat/lng pairs) in radians.

double greatCircleDistanceRads(const LatLng *a, const LatLng *b);

</TabItem> <TabItem value="java">

java

double greatCircleDistance(LatLng point1, LatLng point2, LengthUnit unit);

</TabItem> <TabItem value="javascript">

h3.greatCircleDistance(point1, point2, h3.UNITS.rads)

function example() {
  const point1 = [-10, 0];
  const point2 = [10, 0];
  return h3.greatCircleDistance(point1, point2, h3.UNITS.rads)
}

</TabItem> <TabItem value="python">

h3.great_circle_distance(point1, point2, unit='rads')

</TabItem> <TabItem value="go">

h3.GreatCircleDistanceRads(h3.NewLatLng(latA, lngA), h3.NewLatLng(latB, lngB))

</TabItem> <TabItem value="duckdb">

sql

h3.great_circle_distance(point1, point2, 'rads')

</TabItem> <TabItem value="shell">

$ h3 greatCircleDistanceRads --help
h3: Calculates the 'great circle' or 'haversine' distance between two lat, lng points, in radians
H3 4.1.0

	greatCircleDistanceRads	Calculates the 'great circle' or 'haversine' distance between two lat, lng points, in radians
	-i, --file <FILENAME>	The file to load the coordinates from. Use -- to read from stdin.
	-c, --coordinates <ARRAY>	The array of coordinates to convert. Up to 1500 characters.
	-h, --help	Show this help message.

bash

$ h3 greatCircleDistanceRads -c "[[-10, 0], [10, 0]]"
0.3490658504

</TabItem> </Tabs>

describeH3Error

Provides a human-readable description of an H3Error error code.

char *describeH3Error(H3Error err);

This function cannot fail, as it just returns a string stating that the H3Error value is itself invalid and does not allocate memory to do so. Do not call free on the result of this function.

</TabItem> <TabItem value="javascript">

:::note

Just read the .message property from the caught error, instead.

:::

function example() {
  let errorMessage = ""
  try {
    h3.cellToChildrenSize("asdf", 9);
  } catch (e) {
    errorMessage = e.message;
  }
  return errorMessage;
}

</TabItem> <TabItem value="shell">

$ h3 describeH3Error --help
h3: Returns a description of the provided H3 error code number, or indicates the number is itself invalid.
H3 4.1.0

	describeH3ErrorReturns a description of the provided H3 error code number, or indicates the number is itself invalid.
	-e, --error <CODE>	Required. H3 Error code to describe
	-h, --help	Show this help message.

bash

$ h3 describeH3Error -e 5
Cell argument was not valid

</TabItem> </Tabs>