Mar 112015

Factual is a geographical database of places, services, points of interest and landmarks that is made available for free through their Application Programming Interface (API)

This post explains how to use a PHP library to access this database, the characteristics of the service, and the details on the content that can be retrieved from the Factual API.

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 Posted by at 9:57 am
Mar 112015

A website with information of any kind about a certain geographical location might find interesting to include a list of places, points of interest, businesses and services available in that area.

Yelp is one of the possible choices, together with Google Places, Facebook, etc. for a service provider that implements an API that can be used to retrieve that kind of information. This post explains how to query the Yelp API from a PHP script to obtain a list of nearby places.

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 Posted by at 9:43 am
Jan 192015

Other posts in this blog have already covered the procedure to add an interactive map to a web page either using the Google Maps API or else the HERE Maps API.

Leaflet is an open source alternative equally valid to put a map on a page. The Leaflet API allows adding our own information layers to the map, customize the design, and adapt the map to our requirements in other ways.

This post provides an introduction to the main characteristics and functionality of Leaflet.

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 Posted by at 6:28 pm
Oct 142014

The shapefile (SHP) format is one of the most commonly used data formats in Geographical Information Systems (GIS). Most geographical information editing tools, including free open source tools such as QGIS, can read and generate files in shapefile format.

But sometimes it may be necessary, or simply desirable, to use other formats for the handling of geographical information. One of the most popular formats used in the development of web applications is GeoJSON, that can be directly processed in javascript.

This post explains by means of an example how to convert a file from SHP to GeoJSON format.

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 Posted by at 11:30 am
Dec 142012

Google maps gives users validated with a Google account the possibility to add annotations to a map, to mark places, as well as to highlight paths and closed areas.

The Google maps API also allows to add annotations to the map using javascript. This post reviews how to create these custom maps, both in the Google Maps frontend and by using the API.

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 Posted by at 7:52 am