Smoothed standard deviation changing rate. Interpretation of the indicator values:
The indicator uses the SmoothAlgorithms.mqh library classes (copy it to <terminal_data_folder>\MQL5\Include). The classes were described in detail in the Averaging Price Series for Intermediate Calculations Without Using Additional Buffers article.

Fig.1. Indicator XStdDevSpeed
Tradotto dal russo da MetaQuotes Ltd.
Codice originale https://www.mql5.com/ru/code/20655
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