PolygonAngle

PolygonAngle[poly] gives a list of angles at the vertex points of poly.

PolygonAngle[poly,p] gives the angle at the vertex point p of a polygon poly.

PolygonAngle[poly,i] gives the angle at the point pi of poly in canonical form Polygon[{p1,…,pn},data].

PolygonAngle[…,"spec"] gives the angle specified by "spec".

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