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Arcpy.sa.ExtractByPolygon doesn't support Polygon class or multiple polygons

Question asked by flspat on Mar 23, 2016
Latest reply on Mar 23, 2016 by flspat

The help document for ExtractByPolygon (http://desktop.arcgis.com/en/arcmap/10.3/tools/spatial-analyst-toolbox/extract-by-polygon.htm) states:

 

"A polygon (or polygons) that defines the area of the input raster to be extracted.

Each polygon part is a list of vertices defined by Point classes. Optionally a Polygon class can be used to define a list of polygon parts."

 

However the tool fails if the parameter is an arcpy.Polygon class. Is a polygon class really supported? It would be much easier than extracting out the points for the polygon part into a new list...

 

Also, the document seems to indicate that multiple polygons can be used at one time: See the first line of the parameter description and line below clearly shows a list of multiple lists

 

"form of the object is:

[[point(x1,y1), point(x2,y2), point(xn,yn), ..., point(x1,y1)], [point(x'1,y'1), point(x'2,y'2), point(x'n,y'n), ..., point(x'1,y'1)], ...]"

 

The tools fails when the list contains multiple lists of points.

 

Is the documentation wildly incorrect or the tool broken or am I using it correctly?

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