Kay_StochasticRSI

//@version=2
//vma function is originally written by @LazyBear
//Stochastic RSI code taken from stochcharts.com
//Merging both is my brain child. (Unless someone have already thought that) :)

study(title="Kay_StochasticRSI", shorttitle="Kay_StochRSI", precision=5)
smoothK = input(3, title="Smooth K", minval=1)
smoothD = input(3, title="Smooth D", minval=1)
lengthRSI = input(14, title="RSI", minval=1)
ls = input(14, title="Stoch", minval=1)
src = input(close, title="Source")

vma(src, l) => 
    k = 2.0/(l+1)
    pdm = max((src - src[1]), 0)
    mdm = max((src[1] - src), 0)
    pdmS = ((1 - k)*nz(pdmS[1]) + k*pdm)
    mdmS = ((1 - k)*nz(mdmS[1]) + k*mdm)
    s = pdmS + mdmS
    pdi = pdmS/s
    mdi = mdmS/s
    pdiS = ((1 - k)*nz(pdiS[1]) + k*pdi)
    mdiS = ((1 - k)*nz(mdiS[1]) + k*mdi)
    d = abs(pdiS - mdiS)
    s1 = pdiS + mdiS
    iS = ((1 - k)*nz(iS[1]) + k*d/s1)
    hhv = highest(iS, l) 
    llv = lowest(iS, l) 
    d1 = hhv - llv
    vI = (iS - llv)/d1
    vma=(1 - k*vI)*nz(vma[1]) + k*vI*src
    vma

//First calculate RSI
rsi = rsi(src, lengthRSI)

//Calculate stocastic using rsi as series instead of close
st = ((rsi - lowest(rsi, ls))/(highest(rsi, ls) - lowest(rsi, ls))) * 100
//smooth out Stoch using variable moving average instead of simple moving average (no idea why I did it)
k = vma(st, smoothK)
//Smooth out K using again vma to get D
d = vma(k, smoothD)

//Color calculation.
kC=(k > k[1]) ? green : (k<k[1]) ? red : (k==k[1]) ? blue : black
plot(k, color=kC, transp=0)
plot(d, color=orange)
h0 = hline(80)
h1 = hline(20)
fill(h0, h1, color=purple, transp=80)