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Calculate Vector Data for Points Along a Small Circle

You can calculate vector data for points along a small circle in two ways. If you have a center point and a known radius, use scircle1; if you have a center point and a single point along the circumference of the small circle, use scircle2. For example, to get data points describing the small circle at 10° distance from (67°N, 135°W), use the following:

[latc,lonc] = scircle1(67,-135,10);

To get the small circle centered at the same point that passes through the point (55°N,135°W), use scircle2:

[latc,lonc] = scircle2(67,-135,55,-135);

The scircle1 function also allows you to calculate points along a specific arc of the small circle. For example, if you want to know the points 10° in distance and between 30° and 120° in azimuth from (67°N,135°W), simply provide arc limits:

[latc,lonc] = scircle1(67,-154,10,[30 120]);

When an entire small circle is calculated, the data is in polygon format. For all calculated small circles, 100 points are returned unless otherwise specified. You can calculate several small circles at once by providing vector inputs. For more information, see the scircle1 and scircle2 function reference pages. For more information about small circles, see Small Circles.