[PATCH] Simplify distance calculations

[Robert C. Helling]

On 12 Jun 2015, at 23:26, Anton Lundin <glance at acc.umu.se> wrote:

Anton,

> +	// Earth radious is about 111.5 km where i live
> +	return sqrt(lat1.udeg*lat2.udeg + lon1.udeg*lon2.udeg) / 10;

please at least multiply the longitudes with sin(90degrees - latitude) as otherwise you underestimate the distance at the equator and overestimate the distance closer to the poles.

Best
Robert

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Robert C. Helling     Elite Master Course Theoretical and Mathematical Physics  
                      Scientific Coordinator                                   
                      Ludwig Maximilians Universitaet Muenchen, Dept. Physik    
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