.. index:: single: geohash .. _geohash/0:

.. rst-class:: right

object

geohash

Geohash encoder, decoder, adjacency, covering, hierarchy, integer conversion, bit-precision, and geometry covering predicates for geographic(Latitude,Longitude) coordinates.

| Availability: | logtalk_load(geohash(loader))

| Author: Paulo Moura | Version: 1:2:0 | Date: 2026-05-11

| Compilation flags: | static, context_switching_calls

| Implements: | public :ref:`geohash_protocol <geohash_protocol/0>` | Imports: | public :ref:`options <options/0>` | Uses: | :ref:`geospatial <geospatial/0>` | :ref:`list <list/0>` | :ref:`type <type/0>`

| Remarks:

• Alphabet: Uses the standard geohash base-32 alphabet 0123456789bcdefghjkmnpqrstuvwxyz.
• Encoding canonicalization: Encoding canonicalizes longitudes to the [-180.0,180.0[ range, treating 180.0 as -180.0 so equivalent dateline coordinates map to the same geohash.
• Bounding boxes: Decoded cells are represented using bbox(geographic(MinLatitude,MinLongitude),geographic(MaxLatitude,MaxLongitude)).
• Coverage: Bounding-box coverage accepts antimeridian-crossing boxes where the minimum longitude is greater than the maximum longitude.
• Adaptive covering: Adaptive covers use max_precision/1 together with compact/1 and min_precision/1 options.
• Integer representation: Integer geohashes are 5-bit packed base-32 values with an explicit precision argument preserving leading zero groups.
• Geometry covering: Polygon and polyline covering predicates rely on generic geospatial geometry predicates and do not support antimeridian-crossing input geometries.

| Inherited public predicates: |  :ref:`geohash_protocol/0::adjacent/3`  :ref:`geohash_protocol/0::adjacent_bits/4`  :ref:`geohash_protocol/0::adjacent_int/4`  :ref:`geohash_protocol/0::bounding_box/2`  :ref:`geohash_protocol/0::bounding_box_bits/3`  :ref:`geohash_protocol/0::bounding_box_int/3`  :ref:`geohash_protocol/0::cell_dimensions/3`  :ref:`options_protocol/0::check_option/1`  :ref:`options_protocol/0::check_options/1`  :ref:`geohash_protocol/0::children/2`  :ref:`geohash_protocol/0::common_prefix/3`  :ref:`geohash_protocol/0::compress/2`  :ref:`geohash_protocol/0::covering/3`  :ref:`geohash_protocol/0::covering/4`  :ref:`geohash_protocol/0::decode/2`  :ref:`geohash_protocol/0::decode_bits/3`  :ref:`geohash_protocol/0::decode_int/3`  :ref:`options_protocol/0::default_option/1`  :ref:`options_protocol/0::default_options/1`  :ref:`geohash_protocol/0::encode/3`  :ref:`geohash_protocol/0::encode_bits/3`  :ref:`geohash_protocol/0::encode_int/3`  :ref:`geohash_protocol/0::expand/2`  :ref:`geohash_protocol/0::expand_int/3`  :ref:`geohash_protocol/0::geohash_to_int/2`  :ref:`geohash_protocol/0::int_to_geohash/3`  :ref:`geohash_protocol/0::neighbors/2`  :ref:`geohash_protocol/0::neighbors_bits/3`  :ref:`geohash_protocol/0::neighbors_int/3`  :ref:`options_protocol/0::option/2`  :ref:`options_protocol/0::option/3`  :ref:`geohash_protocol/0::parent/2`  :ref:`geohash_protocol/0::polygon_covering/4`  :ref:`geohash_protocol/0::polyline_covering/4`  :ref:`geohash_protocol/0::precision/3`  :ref:`geohash_protocol/0::valid_geohash/1`  :ref:`options_protocol/0::valid_option/1`  :ref:`options_protocol/0::valid_options/1`  

.. contents:: :local: :backlinks: top

Public predicates

(no local declarations; see entity ancestors if any)

Protected predicates

(no local declarations; see entity ancestors if any)

Private predicates

(no local declarations; see entity ancestors if any)

Operators

(none)

.. seealso::

:ref:`geohash_protocol <geohash_protocol/0>`, :ref:`geospatial <geospatial/0>`