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Version: 4.x

Index inspection functions

These functions provide metadata about an H3 index, such as its resolution or base cell, and provide utilities for converting into and out of the 64-bit representation of an H3 index.

getResolution

Returns the resolution of the index. (Works for cells, edges, and vertexes.)

int getResolution(H3Index h);

getBaseCellNumber

Returns the base cell number of the index. (Works for cells, edges, and vertexes.)

int getBaseCellNumber(H3Index h);

stringToH3

Converts the string representation to H3Index (uint64_t) representation.

H3Error stringToH3(const char *str, H3Index *out);

Returns 0 (E_SUCCESS) on success.

h3ToString

Converts the H3Index representation of the index to the string representation.

H3Error h3ToString(H3Index h, char *str, size_t sz);

str must be at least of length 17. Returns 0 (E_SUCCESS) on success.

isValidCell

Returns non-zero if this is a valid H3 cell index.

int isValidCell(H3Index h);

isResClassIII

Returns non-zero if this index has a resolution with Class III orientation.

int isResClassIII(H3Index h);

isPentagon

Returns non-zero if this index represents a pentagonal cell.

int isPentagon(H3Index h);

getIcosahedronFaces

Find all icosahedron faces intersected by a given H3 cell. Faces are represented as integers from 0-19, inclusive.

H3Error getIcosahedronFaces(H3Index h, int* out);

Face values are placed in the array out. out must be at least length of maxFaceCount(h). The array is sparse, and empty (no intersection) array values are represented by -1.

Returns 0 (E_SUCCESS) on success.

maxFaceCount

Returns the maximum number of icosahedron faces the given H3 index may intersect.

H3Error maxFaceCount(H3Index h3, int *out);

Returns 0 (E_SUCCESS) on success.