Nadex Fx Volume Indicator Vv1

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//  ©Vdubus http://www.vdubus.co.uk/
//Nadex Fx Volume Indicator Vv1
//Original source code: Pip Foundry - Forex Market Volume from IDC
//modified fx pairs to corrospond with Nadex spot/fx instruments // http://www.nadex.com/trade-spot-forex.html
study(title="Nadex Fx Volume Indicator Vv1", shorttitle="Nadex_Fx_Volume_Vv1")
ema = input(true)
fxpairs =
	  ticker == "EURUSD" ? "FX_IDC:EURUSD" : //1
	  ticker == "EURUSD" ? "FX_IDC:EURGBP" : //2
	  ticker == "EURJPY" ? "FX_IDC:EURJPY" : //3
	  ticker == "USDJPY" ? "FX_IDC:USDJPY" : //4
	  ticker == "USDCAD" ? "FX_IDC:USDCAD" : //5
	  ticker == "USDCHF" ? "FX_IDC:USDCHF" : //6
	  ticker == "GBPUSD" ? "FX_IDC:GBPUSD" : //7
	  ticker == "GBPJPY" ? "FX_IDC:GBPJPY" : //8
	  ticker == "AUDJPY" ? "FX_IDC:AUDJPY" : //9
	  ticker == "AUDUSD" ? "FX_IDC:AUDUSD" : //10
	  "                                  "
//----------------------------------------------------------------------------//
src = security(fxpairs, period, volume, false)
plot(src, color = open > close ? #5F107C : #DF0174, style=histogram, linewidth=3, title="Bar colour")
plot(ema ? ema(src, 21) : na, style=line, linewidth=2, color=navy, title="EMA")
//============================================================================//