Friday, February 09, 2007

Degrees of X and Y

I've made maps for a living for ten years now, and I only just realized the source of my coordinate dyslexia.

Image Source: Wikipedia
In geometry we are taught the Cartesian coordinate system. The X-axis is horizontal, the Y-axis vertical, such that (2,3) in the image is two right, three up.

In cartography most locations are plotted by latitude and longitude. Points are given as 43.45º North, 114.77º West or 43.45º,-114.77º.

Only this morning, writing X,Y in my code and watching it map off the surface of the earth that I realized the latitude and longitude are presented as Y,X. I have no idea how it took me ten years to realize why I was always getting that backward.

Here I thought it was just my numeric dyslexia.