topic Re: Is there a method in C# that will convert degrees into kilometers? in ArcGIS Runtime SDK for WPF (Retired) Questions

Is there a method in C# that will convert degrees into kilometers?

EzraSidran — Mon, 25 Feb 2013 19:49:11 GMT

Hi!

Is there a method in C# that will convert degrees (at a given longitude) to kilometers?

Thanks!

Re: Is there a method in C# that will convert degrees into kilometers?

ShaharBukra — Tue, 26 Feb 2013 12:21:34 GMT

You will need to project your coordinate system to metric one, and then you will ba able to calc it witout any problem

Re: Is there a method in C# that will convert degrees into kilometers?

EzraSidran — Tue, 26 Feb 2013 12:40:14 GMT

Actually, I already have the value I need converted.
This is not going to be drawn on the screen.

Basically, I have two values:

float length, width;

Both of these values are in degrees at longitude X and a latitude Y.

What I need is a function that given the longitude and latitude convert to kilometers:

ConvertDegreesToKM(length, X, Y);
ConvertDegreesToKM(width, X, Y);

There's got to be some method to do this buried in ArcGIS because it automatically displays a kilometer scale in the corner of the map.

Re: Is there a method in C# that will convert degrees into kilometers?

DominiqueBroux — Mon, 04 Mar 2013 11:14:07 GMT

A degree of latitude is approximately 111Km.
A degree of longitude is approximately 111Km at equator and decreases to zero as the meridians converge to the poles. The value is depending on the latitude and is approximately 111Km*cos(latitude).

Re: Is there a method in C# that will convert degrees into kilometers?

EzraSidran — Mon, 04 Mar 2013 11:38:41 GMT

A degree of latitude is approximately 111Km.
A degree of longitude is approximately 111Km at equator and decreases to zero as the meridians converge to the poles. The value is depending on the latitude and is approximately 111Km*cos(latitude).

Thanks. I've looked this up at http://www.zodiacal.com/tools/lat_table.php and, for example, it gave me a chart. I was hoping that there was some built in function.

I'll use your cos method.