The Polar chart shows data in circular plot area in polar coordinates where each data point
is represented by a distance/radius and an angle, beginning of the coordinate system.
A point's location in the polar coordinate systems is defined by the Value
property of the PolarSeriesItem which determines the radial coordinate (the radius) and the
Angle property which determines the angular coordinate.
RadHtmlChart supports three types of Polar series. They are only different in the graphical
primitives that are drawn. The primitives are a polyline, polygon and point.
PolarAreaSeries — in this series type the data points are connected with
straight line segments that enclose a filled area together with the chart pole.
PolarLineSeries — this series type is represented on the chart as data points connected with straight line segments.
PolarScatterSeries — this series type is represented on the chart as non-connected data points.