BUY & SELL VOLUME PRESSURE by @XeL_Arjona

//	* BUY & SELL PRESSURE VOLUME PRESSURE
//    Ver. 1.00.beta1.27.07.2015
//    By Ricardo M Arjona @XeL_Arjona
//	
//		DISCLAIMER:
//
//      The Following indicator/code IS NOT intended to be
//      a formal investment advice or recomendation by the
//      author, nor should be construed as such. Users
//      will be fully responsible by their use regarding 
//      their own trading vehicles/assets.
//
//		The embedded code and ideas within this work are 
//		FREELEY AND PUBLICLY available on the Web
//		for NON LUCRATIVE ACTIVITIES and must remain as is.
//
//		Pine Script code MOD's and addaptations by @XeL_Arjona 
//      with special mention in regard of:
//      + Buy (Bull) and Sell (Bear) "Power Balance Algorithm" by:
//          Stocks & Commodities V. 21:10 (68-72):
//          "Bull And Bear Balance Indicator by Vadim Gimelfarb"
//      + Normalization (Filter) from Karthik Marar's VSA work:
//          http://karthikmarar.blogspot.mx
//      + Buy to Sell Convergence / Divergence and Volume Pressure
//        Conunterforce Histogram Ideas by:   @XeL_Arjona
//
//      WHAT IS THIS?
//
//      The following indicators try to acknowledge in a K-I-S-S
//      approach to the eye (Keep-It-Simple-Stupid), the two most
//      important aspects of nearly every trading vehicle:
//           -- PRICE ACTION IN RELATION BY IT'S VOLUME --
//
//      A) Volume Pressure Histogram:
//         Columns plotted in positive are considered the dominant
//      Volume Force for the given period.  All "negative" columns
//      represents the counterforce Vol.Press against the dominant.
//
//      B) Buy to Sell Convergence / Divergence:
//         It's a simple addaptation of the popular "Price
//      Percentage Oscilator" or MACD but taking Buying Pressure
//      against Selling Pressure Averages, so given a Positive 
//      oscilator reading (>0) represents Bullish dominant Trend
//      and a Negative reading (<0) a Bearish dominant Trend.
//      Histogram is the diff between RAW Volume Pressures
//      Convergence/Divergence minus Normalized ones (Signal)
//      which helps as a confirmator.
//
//      C) Volume bars are by default plotted from RAW Volume
//      Pressure algorithms, but they can be as well filtered
//      with Karthik Marar's approach against a "Total Volume
//      Average" in favor to clean day to day noise like HFT.
//
//      D) ALL NEW IDEAS OR MODIFICATIONS to these indicators are
//      Welcome in favor to deploy a better and more accurate readings.
//      I will be very glad to be notified at Twitter: @XeL_Arjona
//
//      Any important adition to this work MUST REMAIN
//      PUBLIC by means of CreativeCommons CC & TradingView.
//      2015
//		
//////////////////////////////////////////////////////////////////
study("BUY & SELL VOLUME PRESSURE by @XeL_Arjona", shorttitle="BSP_XeL", precision=0)
signal = input(title="Base for FastMA Periods:", type=integer, defval=3)
long = input(title="Buy to Sell Conv/Div Lookback:", type=integer, defval=27)
norm = input(false, title="Normalized (Filtered) Version:")
vmacd = input(false, title="Buy to Sell Convergence/Div OSC:")
//vapi = input(false, title="Display Acc/Dist % :")
vol = iff(volume > 0, volume , 1)
// PRESSURE ALGORITHMS AND VARIABLES
TR = atr(1)
// Bull And Bear "Power-Balance" by Vadim Gimelfarb Algorithm's
BP =    iff(close<open,     iff(close[1]<open,  max(high-close[1], close-low), 
                                                    max(high-open, close-low)),
            iff(close>open,     iff(close[1]>open,  high-low, 
                                                    max(open-close[1], high-low)),
            iff(high-close>close-low, iff(close[1]<open,    max(high-close[1],close-low),
                                                            high-open),
            iff(high-close<close-low, iff(close[1]>open,    high-low,
                                                            max(open-close[1], high-low)),
            iff(close[1]>open,  max(high-open, close-low),
            iff(close[1]<open,  max(open-close[1], high-low),
        high-low))))))
SP =    iff(close<open,     iff(close[1]>open,  max(close[1]-open, high-low),
                                                    high-low),
            iff(close>open,     iff(close[1]>open,  max(close[1]-low, high-close),
                                                    max(open-low, high-close)),
            iff(high-close>close-low,   iff(close[1]>open,  max(close[1]-open, high-low),
                                                            high-low),
            iff(high-close<close-low,   iff(close[1]>open,  max(close[1]-low, high-close),
                                                            open-low),
            iff(close[1]>open,  max(close[1]-open, high-low),
            iff(close[1]<open,  max(open-low, high-close),
        high-low))))))
TP = BP+SP
// RAW Pressure Volume Calculations
BPV = (BP/TP)*vol
SPV = (SP/TP)*vol
TPV = BPV+SPV
BPVavg = ema(ema(BPV,signal),signal)
SPVavg = ema(ema(SPV,signal),signal)
TPVavg = ema(wma(TPV,signal),signal)
// Karthik Marar's Pressure Volume Normalized Version (XeL-MOD.)
VN = vol/ema(vol,long)
BPN = ((BP/ema(BP,long))*VN)*100
SPN = ((SP/ema(SP,long))*VN)*100
TPN = BPN+SPN
nbf = ema(wma(BPN,signal),signal)
nsf = ema(wma(SPN,signal),signal)
tpf = ema(wma(TPN,signal),signal)
ndif = nbf-nsf
// Conditional Selectors for RAW/Norm
BPc1 = BPV>SPV ? BPV : -abs(BPV)
BPc2 = BPN>SPN ? BPN : -abs(BPN)
SPc1 = SPV>BPV ? SPV : -abs(SPV)
SPc2 = SPN>BPN ? SPN : -abs(SPN)
BPcon = norm ? BPc2 : BPc1
SPcon = norm ? SPc2 : SPc1
BPAcon = norm ? nbf : BPVavg
SPAcon = norm ? nsf : SPVavg
TPAcon = norm ? tpf : TPVavg
// Volume Pressure Convergence Divergence by XeL_Arjona
vpo1 = (( sum(BPVavg,long)-sum(SPVavg,long))/sum(TPVavg,long))*100
vpo2 = (( sum(nbf,long)-sum(nsf,long))/sum(tpf,long))*100 //ema(wma(vmcdt,signal),signal)
vph = nz((vpo1 - vpo2),0)
// Plot Indicator
histC = vph > vph[1] ? blue:#BA00AA
Vpo1C = vpo1 > 0 ? green:red
Vpo2C = vpo2 > 0 ? green:red
plot(vmacd ? na:SPcon, color=red, title="SELLING", style=columns, linewidth=3, transp=80)
plot(vmacd ? na:BPcon, color=green, title="BUYING", style=columns, linewidth=3, transp=80)
plot(vmacd ? na:SPAcon, color=red, title="SPAvg", style=line, linewidth=2) //ema(BearPower*SPV,signal)
plot(vmacd ? na:BPAcon, color=green, title="BPAvg", style=line, linewidth=2) //ema(BullPower*BPV,signal)
plot(vmacd ? vpo1:na, color=Vpo1C,title="VPO1", style=line, linewidth=3)
plot(vmacd ? vpo2:na, color=Vpo2C,title="VPO2", style=line, linewidth=1)
plot(vmacd ? vph:na, color=histC, title="VPH", style=columns, linewidth=3, transp=80)