rwmeier

Polygon Measure Results are Not the Same - ESRI samples

Discussion created by rwmeier on Jul 31, 2012
Latest reply on Nov 19, 2012 by rwmeier
I am trying to do a bit of simple area measuring using the geometryService.areasAndLengths and was not getting the expected result, so I started looking at the online samples and found the samples do not give the same result when measuring the same area.

These two samples:
http://help.arcgis.com/en/webapi/javascript/arcgis/demos/widget/widget_measurement.html

http://help.arcgis.com/en/webapi/javascript/arcgis/demos/util/util_measurepoly.html

If you go to this coordinate : 38.8776559269747,-94.75016940780633, which is in Olathe, KS, where most of the main thoroughfares are on square miles and measure a square mile you get 2 different results.

The Widget correctly measures a square mile as 1, the other using geometryService.areasAndLengths, measures a square mile to about 1.6 sqmi.

Why?

I posted on a similar thing in the Silverlight forum - http://forums.arcgis.com/threads/34484-Geometry-Service-Areas-and-Length

*** Edit - I went back and looked at my Silvelright code, I had to project the measure geometry from mercator to geographic then to Equal Area in order to get the correct measurement. Still the fact remains that the sample code using geometryService.areasAndLengths does not show any projecting and gives an incorrect result.

Since both JS and Silverlight use the same REST geometry service, is it an issue with the REST geometry service?

Any help is appreciated.

-bert

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