Measure positive upward movement.
Syntax: PDI(Length, Smoothing, Interval, [Ref], [Symbol])
Length = Required.
Smoothing = Required.
Interval = Required.
[Ref] = Optional.
[Symbol] = Optional.
Examples:
PDI(14, 14, 5, 0, YHOO)
Positive Directional Indicator for YHOO for the current 5-Minute Bar where the Length = 14 and the Smoothing = 14.