Calculates the Parabolic Stop and Reverse system indicator and returns its value.
[in] Symbol name on the data of which the indicator will be calculated. NULL means the current symbol.
[in] Timeframe. It can be any of ENUM_TIMEFRAMES enumeration values. 0 means the current chart timeframe.
[in] The step of price increment, usually 0.02.
[in] The maximum step, usually 0.2.
[in] Index of the value taken from the indicator buffer (shift relative to the current bar the given amount of periods ago).
Numerical value of the Parabolic Stop and Reverse system indicator.