# freeware kp_PPO – Plots the Percent Price Oscillator on a daily chart.
# The PPO is similar to then MACD except the MACD is
# based on absolute values whereas the PPO is relative
# to its average price.

declare lower;

input fastPeriod = 8;
input slowPeriod = 17;
input signalPeriod = 9;
input price = close;
input showSignals = yes;

def fastEma = ExpAverage(price, fastPeriod);
def slowEma = ExpAverage(price, slowPeriod);

def periodOK = fastPeriod < slowPeriod;
AddLabel(!periodOK, “ERROR: fastPeriod MUST be less than slowPeriod”);

def _ppo = if periodOK then (((fastEma – slowEma) / slowEma) * 100) else 0;
def _signal = ExpAverage(_ppo, signalPeriod);

plot PPO = _ppo;
AddLabel(yes, "PPO: " + AsText(PPO, NumberFormat.TWO_DECIMAL_PLACES) + (if PPO > PPO[1] AND PPO > _SIGNAL then "  rising" else if PPO < PPO[1] then "  falling" else ""), CreateColor(0, 1, 1));
AddLabel(yes, "ppo:  " + AsText(PPO[1], NumberFormat.TWO_DECIMAL_PLACES) + (if PPO[1] > PPO[2] then "  last week rising" else if PPO[1] < PPO[2] then "  last week falling" else ""), CreateColor(0, 1, 1));


PPO.SetLineWeight(3);
PPO.HideBubble();




plot PPOEMA = _signal;
PPOEMA.SetDefaultColor(Color.RED);

plot zeroLine = 0;
zeroLine.HideBubble();
zeroLine.SetDefaultColor(Color.LIGHT_GRAY);

plot PPOHistogram = _ppo – _signal;
PPOHistogram.SetPaintingStrategy(PaintingStrategy.HISTOGRAM);
PPOHistogram.DefineColor(“Up”, Color.UPTICK);
PPOHistogram.DefineColor(“Down”, Color.DOWNTICK);
PPOHistogram.DefineColor(“Flat”, Color.GRAY);
PPOHistogram.AssignValueColor( if (PPOHistogram > PPOHistogram[1] && PPOHistogram > 0) then PPOHistogram.Color(“Up”) else
if (PPOHistogram < PPOHistogram[1] && PPOHistogram < 0) then PPOHistogram.Color(“Down”) else
PPOHistogram.Color(“Flat”)
);
PPOHistogram.HideBubble();
PPOHistogram.SetLineWeight(5);

plot UpSignal = if PPOHistogram crosses above zeroLine then zeroLine else Double.NaN;
plot DnSignal = if PPOHistogram crosses below zeroLine then zeroLine else Double.NaN;

UpSignal.SetHiding(!showSignals);
DnSignal.SetHiding(!showSignals);

UpSignal.SetDefaultColor(Color.UPTICK);
UpSignal.SetPaintingStrategy(PaintingStrategy.ARROW_UP);
DnSignal.SetDefaultColor(Color.DOWNTICK);
DnSignal.SetPaintingStrategy(PaintingStrategy.ARROW_DOWN);