[OpenLayers-Users] area enclosed by linestring

[Jim White]

I tried that first. It was way off. I think by a factor of cos(lat)**2.



On 01/15/2012 03:24 PM, Toby Reinicke wrote:
> Do you have the same issue if you just use ring.getArea() function?
>
> On 15 Jan 2012, at 18:31, Jim White<jbw2003 at earthlink.net>  wrote:
>
>> Hi,
>>
>> I use this to calculate the number of acres enclosed by a linestring:
>>
>> ring = new OpenLayers.Geometry.LinearRing(geometry.getVertices());
>> area = ring.getGeodesicArea(new OpenLayers.Projection("EPSG:900913"));
>> area = Math.floor(Math.abs(area*0.000247105381));
>>
>> The calculated area consistently produces results that are 2-3% too small. Is this an error in my code or is my data the problem?
>>
>> Thanks,
>> Jim White
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