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Comment by jmwilson | Hacker News Reader

The author says neither is right, but clearly prefers lon, lat ordering.

"Geographical tradition favors lat, lon. Math and software prefer lon, lat."

But why does math and software prefer lon, lat? Unlike endianness, where it appears little-endian is the better choice at the hardware level, I'm drawing a blank why one ordering is better for computation.

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This part of the FAQ links the author's explanation of his preference.

> Do you have a preference? Yes I do: longitude, latitude.

http://macwright.org/2016/07/15/longitude-latitude-is-the-ri...

The bullet points:

* Almost every geospatial format puts longitude first

* Almost all open source software uses longitude, latitude ordering

* longitude-first is the equivalent of XY ordering

One reason that comes to mind is that (longitude, latitude, altitude) is right handed, and we tend to prefer right handed coordinate systems.

I agree with the point, but software has at times frustratingly used left-handed coordinates for drawing on screens. DirectX and browsers' use of `z` come to mind.

When plotted on a mercator-style map, longitude corresponds to X and latitude corresponds to Y, with X, Y being the usual order for coordinates. (That's my guess, anyway.)

The X and Y you describe are also conventions based on putting north at the top of a map, and really only map one-to-one in Mercator projection anyway.

Well, by standard convention longitude is labeled θ and latitude is labeled φ. People think more about θ because it also appears in two-dimensional polar coordinates.

But in math you care far more about labeling the angles correctly than about which order you list them in.

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