src/statistics/directional/circular_standard_deviation.js

Circular Standard Deviation

From Kanti V. Mardia & Peter E. Jupp, "Directional Statistics", Wiley, 2000

mctad.circularStandardDeviation = function (data) {

The circular standard deviation is undefined if the data is not in an Array of 1 or more elements.

if (!Array.isArray(data) || data.length === 0) { return undefined; }

Mardia & Jupp equation 2.3.11 Depends on meanResultantLength

return Math.sqrt( -2.0 * mctad.getBaseLog(10, 1 - mctad.meanResultantLength(data)) ); };