Calculates the Aroon index based on the closing prices and a given period to analyse.

Extracts an archive downloaded from the gcp bucket.

Sigmoid function based this formula: https://de.wikipedia.org/wiki/Sigmoidfunktion Transforming value range from [0,1] to [-1,1].

Removes 0 Values of an Array and returnes the clean array as well as the index of the removed items.

Calculates the SMA of the given input array with the given window size n.