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@calebwoods
Created November 26, 2012 20:02
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Test of acreage calculation for polygons that span more than 1 UTM zone.
// Zone spanning polygon
{
"type": "MultiPolygon",
"coordinates": [
[
[
[-90.00575, 35.99485],
[-89.99339, 35.99485],
[-89.99339, 36.00481],
[-90.00575, 36.00481],
[-90.00575, 35.99485]
]
]
]
}
// Using Zone 15 projection
// => 304.64208165875334 acres
// Using Zone 16 projection
// => 304.64176688085104 acres
// Calculations with Polygons split so each is contained by the UTM zone.
// Zone 15
{
"type": "MultiPolygon",
"coordinates": [
[
[
[-90.00575, 35.99485],
[-90.0, 35.99485],
[-90.0, 36.00481],
[-90.00575, 36.00481],
[-90.00575, 35.99485]
]
]
]
}
// => 141.7220884545912 acres
// Zone 16
{
"type": "MultiPolygon",
"coordinates": [
[
[
[-89.999999999, 35.99485],
[-89.99339, 35.99485],
[-89.99339, 36.00481],
[-89.999999999, 36.00481],
[-89.999999999, 35.99485]
]
]
]
}
// => 162.9186747197805 acres
// Partials Combined
// => 304.6407631743717 acres
// Original Non-Split polygon Zone 15
// => 304.64208165875334 acres
// Original Non-Split polygon Zone 16
// => 304.64176688085104 acres
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