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========================
OHLC - previous period's
========================
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{ Previous period's OHLC v1.0
  Warning: chart's first data bar is ignored.
  Adapted from:
  http://www.metastocktools.com/MACDH/Forex.htm

©Copyright 2004~2006 Jose Silva.
 The grant of this license is for personal use
  only - no resale or repackaging allowed.
 All code remains the property of Jose Silva.
 http://metastocktools.com }

{ User input }
type:=Input("OHLC values: [1]Day, [2]Week, [3]Month, [4]Year",1,4,1);

{ Day's start }
DayStart:=DayOfMonth()<>Ref(DayOfMonth(),-1);

{ Week's start - reference "Calendar Week
 counter" indicator for accurate weekly signals}
WkStart:=DayOfWeek()<Ref(DayOfWeek(),-1);

{ Month's start }
MthStart:=Month()<>Ref(Month(),-1);

{ Year's start }
YrStart:=Year()>Ref(Year(),-1);

{ Selected Daily/Weekly/Monthly/Yearly }
start1:=If(type=1,DayStart,
 If(type=2,WkStart,
 If(type=3,MthStart,YrStart)));
start:=start1 OR Cum(1)=2;

{ Previous period's Open }
Op:=ValueWhen(2,start,O);
Op:=ValueWhen(1,Op<>0,Op);

{ Previous period's High }
Hi:=HighestSince(1,start,H);
Hi:=ValueWhen(1,start,ValueWhen(2,1,Hi));
Hi:=ValueWhen(1,Hi<>0,Hi);

{ Previous period's Low }
Lo:=LowestSince(1,start,L);
Lo:=ValueWhen(1,start,ValueWhen(2,1,Lo));
Lo:=ValueWhen(1,Lo<>0,Lo);

{ Previous period's Close }
Cl:=ValueWhen(1,start1,ValueWhen(2,1,C));
Cl:=ValueWhen(1,Cl<>0,Cl);

{ Plot on price chart }
Op;  { <- Green }
Hi;  { <- Blue }
Lo;  { <- Red }
Cl;  { <- Dk Green }

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