Distance Calculator

I believe that distance calculation is the core of GIS.

Distance calculation lies at the heart of Geographic Information Systems (GIS). It is the golden thread that weaves through every map, analysis, and decision, serving as an invisible ruler that measures not only space but also the connectivity, accessibility, and relationships that shape our world.

Whether it's aiding urban planners in designing efficient transportation networks or helping ecologists understand wildlife migration patterns, distance in GIS acts as a guiding compass—steering us toward informed solutions and deeper insights.

This educational project, inspired by my upcoming book for programmers eager to learn GIS, demonstrates how to build applications that calculate the distance between two points. The current page showcases a prototype based on the Cartesian coordinate system. Please note that distances are expressed in abstract units rather than in Kilometers or Miles, reflecting the use of an imaginary coordinate system. Links provided at the end of each page will lead you to more advanced approaches.

First Point

Map 1

Second Point

Map 2

Straight line between the two points

Note: Calculating distance using the Euclidean method on a Cartesian coordinate system assumes a flat plane. In reality, the Earth is curved, so this method does not account for the planet’s curvature, which can lead to inaccuracies especially over large distances.

For distance calculation based on the Earth's curvature, click below:

Distance Calculator Based on the Curvature of the Earth
from js import document from pyodide import create_proxy import math def cartesian_distance(lat1, lon1, lat2, lon2): dx = lat2 - lat1 dy = lon2 - lon1 return math.sqrt(dx**2 + dy**2) def calculate_distance(event): try: lat1 = float(document.getElementById("FirstLat").value) lon1 = float(document.getElementById("FirstLong").value) lat2 = float(document.getElementById("SecLat").value) lon2 = float(document.getElementById("SecLong").value) except: document.getElementById("result").innerText = "Error: Please enter valid numeric coordinates." return distance = cartesian_distance(lat1, lon1, lat2, lon2) document.getElementById("result").innerText = f"Calculated Distance: {distance:.6f} units" document.getElementById("button").addEventListener("click", create_proxy(calculate_distance))