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Apollo: Where and When

Project: Apollo Abstract GIS-Applications are applications that gathers, manages and analyzes spatial-related data. They are rooted from Geography and is now used in almost all aspects of discipline where Geographic and/or Spatial data manipulation is required. This includes  applications related to  engineering, planning, management, transport/logistics, insurance, telecommunications, and business [ 1 ]. Guttman [ 2 ] started the topic of generalizing B-tree ( a self-balancing  tree data structure  that  maintains sorted data and allows searches, sequential access, insertions, and deletions in  logarithmic time . [ 3 ] ) to index multi-dimensional data (coordinates, polygons, rectangles, among others). Such a step enables the rise of Geo-spatial databases for gathering, analyzing and querying such data (i.e. Esri , GIS-planning  and Database extensions like GeoMesa (for Hadoop), PostGIS (PostgreSQL), Oracle, CouchDB, among others) for a more customized (in case of

Hermes - My Need For An Alternate Key-Value Store

Hermes Yet another concurrent, lightweight, fast and efficient In-Memory Key-Value Store alternative. This was a sub-component of a pet IR system in Go. I thought this is helpful enough and can stand on its own and can help alleviate disk I/O operations (database, file, etc.) in a quite-not-so-small-but-single-machine kind of systems. What makes Hermes unique is its use of the ff: LRFU cache (which makes for a swift transition between LRU and LFU). Bloom filter implementation (Cuckoo Filter, to allow for item deletion in every eviction done by the policy) to avoid caching one-hit-wonders (disabled by default, please see the toml file to enable it) for memory efficiency. HAMT data structure (which makes it memory efficient at a nearly O(1) operation) Use this in your app like so (as embedded): package main import ( "fmt" "github.com/jtejido/hermes/hermes" "github.com/jtejido/hermes/config" "github.com/BurntSushi/to

GeodesyPHP - A Great-Earth Distance library

Geodesy-PHP Geodesy-PHP is a port of some known geodesic/math functions for getting distance from a known point A to a known point B, given their coordinates (good for working out distances between different latitude/longitude data provided by Google Geolocation or any RESTful APIs). It also supports conversion between units of length, Polar position to Cartesian coordinates, and transforming different Reference Datums. It provides distance calculations thru: Spherical Law of Cosines Haversine formula  (Half a Versine - versed sine) Vincenty's formula Thomas' formula Hubeny's formula Andoyer-Lambert's formula Elliptic Distance Forsythe-Andoyer-Lambert Formula Note: This library is a collection that solves the Inverse geodetic problem . Installation: composer require jtejido/geodesy-php Usage Distance Calculation All classes receives and gives all values in  Metre unit of length by default. use Geodesy\Location\LatLong; use Geodes

Basset - Information Retrieval Library in PHP

Basset Basset is a full-text  PHP Information Retrieval library. This is a collection of developments in the field of IR and ported over to PHP for research purposes. Basset provides different ways of searching through documents in a collection (ad-hoc), by applying advanced and experimental IR algorithms and/or techniques gathered from different Research studies and Conferences, most notably: TREC SIGIR ECIR ACM Basics Warning: This is a tool that is continuously under development. Please use this as a research tool for your otherwise special Production needs. Adding Documents Basset manages adding document thru the IndexWriter Class. It processes the documents you'll be adding in and later on commit to an external file. It takes a directory path, and overwrite (they both default to '../index/' and true consecutively). Setting overwrite to false means that you won't be accidentally overwriting any existing index inside the directory. Methods: