ta.pviPositive Volume Index

//@version=6
indicator("Positive Volume Index")

plot(ta.pvi, color=color.yellow)

// the same on pine
f_pvi() =>
    float ta_pvi = 1.0
    float prevPvi = (nz(ta_pvi[1], 0.0) == 0.0) ? 1.0 : ta_pvi[1]
    if nz(close, 0.0) == 0.0 or nz(close[1], 0.0) == 0.0
        ta_pvi := prevPvi
    else
        ta_pvi := (volume > nz(volume[1], 0.0)) ? prevPvi + ((close - close[1]) / close[1]) * prevPvi : prevPvi
    result = ta_pvi

plot(f_pvi())