Version: 4.x

Miscellaneous H3 functions

These functions include descriptions of the H3 grid system.

degsToRads

C
Python
Java
JavaScript (Live)

double degsToRads(double degrees);

note

Use math.radians(degrees) instead.

note

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

h3.degsToRads(degrees)

Live Editor

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

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

Result

Converts degrees to radians.

radsToDegs

C
Python
Java
JavaScript (Live)

double radsToDegs(double radians);

note

Use math.degrees(radians) instead.

note

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

h3.radsToDegs(h)

Live Editor

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

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

Result

Converts radians to degrees.

getHexagonAreaAvgKm2

C
Python
Java
JavaScript (Live)

H3Error getHexagonAreaAvgKm2(int res, double *out);

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

double getHexagonAreaAvg(int res, AreaUnit unit);

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

Live Editor

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

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

Result

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

getHexagonAreaAvgM2

C
Python
Java
JavaScript (Live)

H3Error getHexagonAreaAvgM2(int res, double *out);

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

double getHexagonAreaAvg(int res, AreaUnit unit);

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

Live Editor

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

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

Result

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

cellAreaRads2

C
Python
Java
JavaScript (Live)

H3Error cellAreaRads2(H3Index h, double *out);

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

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

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

Live Editor

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

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

Result

Exact area of specific cell in square radians.

cellAreaKm2

C
Python
Java
JavaScript (Live)

H3Error cellAreaKm2(H3Index h, double *out);

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

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

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

Live Editor

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

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

Result

Exact area of specific cell in square kilometers.

cellAreaM2

C
Python
Java
JavaScript (Live)

H3Error cellAreaM2(H3Index h, double *out);

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

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

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

Live Editor

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

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

Result

Exact area of specific cell in square meters.

getHexagonEdgeLengthAvgKm

C
Python
Java
JavaScript (Live)

H3Error getHexagonEdgeLengthAvgKm(int res, double *out);

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

double getHexagonEdgeLengthAvg(int res, LengthUnit unit);

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

Live Editor

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

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

Result

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

getHexagonEdgeLengthAvgM

C
Python
Java
JavaScript (Live)

H3Error getHexagonEdgeLengthAvgM(int res, double *out);

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

double getHexagonEdgeLengthAvg(int res, LengthUnit unit);

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

Live Editor

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

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

Result

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

edgeLengthKm

C
Python
Java
JavaScript (Live)

H3Error edgeLengthKm(H3Index edge, double *length);

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

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

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

Live Editor

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

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

Result

Exact edge length of specific unidirectional edge in kilometers.

edgeLengthM

C
Python
Java
JavaScript (Live)

H3Error edgeLengthM(H3Index edge, double *length);

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

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

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

Live Editor

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

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

Result

Exact edge length of specific unidirectional edge in meters.

edgeLengthRads

C
Python
Java
JavaScript (Live)

H3Error edgeLengthRads(H3Index edge, double *length);

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

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

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

Live Editor

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

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

Result

Exact edge length of specific unidirectional edge in radians.

getNumCells

C
Python
Java
JavaScript (Live)

H3Error getNumCells(int res, int64_t *out);

h3.get_num_cells(res)

long getNumCells(int res);

h3.getNumCells(res)

Live Editor

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

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

Result

Number of unique H3 indexes at the given resolution.

getRes0Cells

C
Python
Java
JavaScript (Live)

H3Error getRes0Cells(H3Index *out);

h3.get_res0_cells()

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

h3.getRes0Cells()

Live Editor

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

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

Result

All the resolution 0 H3 cell indexes. These are the coarsest cells that can be represented in the H3 system and are the parents of all other cell indexes in the H3 grid system. The returned indexes correspond with the 122 base cells.

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

res0CellCount

C
Python
Java
JavaScript (Live)

int res0CellCount();

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

getPentagons

C
Python
Java
JavaScript (Live)

H3Error getPentagons(int res, H3Index *out);

h3.get_pentagons(res)

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

h3.getPentagons(res)

Live Editor

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

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

Result

All the pentagon H3 indexes at the specified resolution. out must be an array of at least size pentagonIndexCount().

Returns 0 (E_SUCCESS) on success.

pentagonCount

C
Python
Java
JavaScript (Live)

int pentagonCount();

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

greatCircleDistanceKm

C
Python
Java
JavaScript (Live)

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

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

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

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

Live Editor

function example() {
  const point1 = [-10, 0];
  const point2 = [10, 0];
  return 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)
}

Result

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

greatCircleDistanceM

C
Python
Java
JavaScript (Live)

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

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

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

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

Live Editor

function example() {
  const point1 = [-10, 0];
  const point2 = [10, 0];
  return 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);
}

Result

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

greatCircleDistanceRads

C
Python
Java
JavaScript (Live)

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

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

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

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

Live Editor

function example() {
  const point1 = [-10, 0];
  const point2 = [10, 0];
  return 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)
}

Result

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

degsToRads​

radsToDegs​

getHexagonAreaAvgKm2​

getHexagonAreaAvgM2​

cellAreaRads2​

cellAreaKm2​

cellAreaM2​

getHexagonEdgeLengthAvgKm​

getHexagonEdgeLengthAvgM​

edgeLengthKm​

edgeLengthM​

edgeLengthRads​

getNumCells​

getRes0Cells​

res0CellCount​

getPentagons​

pentagonCount​

greatCircleDistanceKm​

greatCircleDistanceM​

greatCircleDistanceRads​

degsToRads

radsToDegs

getHexagonAreaAvgKm2

getHexagonAreaAvgM2

cellAreaRads2

cellAreaKm2

cellAreaM2

getHexagonEdgeLengthAvgKm

getHexagonEdgeLengthAvgM

edgeLengthKm

edgeLengthM

edgeLengthRads

getNumCells

getRes0Cells

res0CellCount

getPentagons

pentagonCount

greatCircleDistanceKm

greatCircleDistanceM

greatCircleDistanceRads