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Task/Averages-Mean-angle/Nim/averages-mean-angle.nim

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+import math, complex
+
+proc rect(r, phi): Complex = (r * cos(phi), sin(phi))
+proc phase(c): float = arctan2(c.im, c.re)
+
+proc radians(x): float = (x * Pi) / 180.0
+proc degrees(x): float = (x * 180.0) / Pi
+
+proc meanAngle(deg): float =
+  var c: Complex
+  for d in deg:
+    c += rect(1.0, radians(d))
+  degrees(phase(c / float(deg.len)))
+
+echo "The 1st mean angle is: ", meanAngle([350.0, 10.0]), " degrees"
+echo "The 2nd mean angle is: ", meanAngle([90.0, 180.0, 270.0, 360.0]), " degrees"
+echo "The 3rd mean angle is: ", meanAngle([10.0, 20.0, 30.0]), " degrees"