Nemo mini-library - introduction and purpose


Petaluma 1

The natural domain of all geographical data is isometric, finite and boundless spheroidal surface of the planet Earth. This is why it is frequently both easier and more useful to build a digital globe, then it is to build a digital map:

Petaluma 2

The traditional method of geographic coordinate recording consists of angular φ and λ (latitude and longitude, respectively). This coordinate form is ill-suited for processing on a digital computer. Specifically, the implementer of any application that handles large volumes of wide area geographic data must find a solution to three fundamental software engineering problems:

Nemo mini-library is a collection of C-language functions, that provides a path to the solution of those problems. It may work effectively for a large number of different geographical applications.

The approach to geographic data representation outlined above provides a sound foundation for implementation of complex, multi-point data objects (multi-point sets, lines, surface areas) and of spatial sorting and searching - both the subject of a different software package (currently under development) from which Nemo mini-library is an excerpt.

This web-page is only a brief outline; the distribution archive includes additional documents and external references. There are also detailed preambles and in-line commentary in each library source code file.

The use of the Nemo mini-library is governed by a BSD-style license, the text of which is included in the distribution archive.

The library is distributed as a .tar archive. There is no "version control" other than a 6-digit (YYMMDD) publication date numeric string in the file name.

Download the library archive (905.1 kB): [nemo-minilib-221007.tar.gz].