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How to adjust the number of blank bars in right margin

The default number of bars shown in the right-hand side of the chart area is defined in Tools->Preferences->Charting:

Blank bars

It is also possible to extend the blank bars area manually. Pressing END key on the keyboard will add 10 extra bars with each keystroke. Pressing HOME will reset the blank bars area back to default value from Preferences.

Number of bank bars can also be controlled using SetChartOptions() function from the code.

SetChartOptions00chartGridMiddle00100 );
PlotClose"Close"colorDefaultstyleBar );

Detailed documentation of SetChartOptions function is available in the manual:
http://www.amibroker.com/f?SetChartOptions

Indicators based on user values rather than standard OHLC prices

Sometimes we may want to calculate indicators based not only on standard OHLC prices but on some other user-definable values. Some functions like RSI or CSI have additional versions (RSIa, CCIa respectively) that accept custom input array. In this case it is very easy to calculate the indicator based on user defined value. For example RSI from average of High and Low prices could be written as follows:

customArray = ( High Low ) / 2;

PlotRSIacustomArray14 ), "RSI from (H+L)/2"colorRed );

But many of the built-in indicators available in AFL as functions refer indirectly to standard OHLC arrays and their parameters do not offer array argument as one of inputs.

Fortunatelly there is an easy way to provide custom array as input for any other built-in functions. For this purpose, it is enough to override OHLC arrays (or just Close if the indicator only uses Close as input) within the code before calling given function and assign our custom array. As a simple example, let us consider calculating MACD indicator out of average of High and Low prices as input.

procedure SaveRestorePricesDoSave )
{
  global 
SaveOSaveHSaveLSaveCSaveV;
  
  if( 
DoSave )
  {
     
SaveO Open;
     
SaveH High;
     
SaveL Low;
     
SaveC Close;
     
SaveV Volume;
  }
  else
  {
    
Open SaveO;
    
High SaveH;
    
Low SaveL;
    
Close SaveC;
    
Volume SaveV;
  }
}

// save OHLCV arrays
SaveRestorePricesTrue );

// calculate our array
customArray = ( High Low ) / 2;

// override built-in array(s)
Close customArray;

// calculate our function, MACD and Signal in this case
PlotMACD1226 ), "MACD"colorRed );
PlotSignal1226), "Signal"colorBlue );

// restore OHLCV arrays
SaveRestorePricesFalse );

The code first calculates the custom array (we use just use average of High and Low prices in this example, but of course the calculations may be more complex), then assigns the result of these calculations to Close overriding the regular values stored in close array. Then – when we call MACD() function which uses Close as input – it will be based on the modified values.

The above operations do not affect the underlying database at all – the prices are overridden only for the purpose of calculation of this particular formula and other charts / indicators are not affected at all.

How to sync a chart with the Analysis window

When we want to sync a chart with the selected symbol in the Analysis results list, it is enough just to double-click on the particular line in the list and AmiBroker will automatically switch the selected symbol and interval to match the Analysis window.

Sync by double click

Additionally, when we browse through Scan or Backtest results, double-clicking would be an equivalent of Show arrows for all raw signals option from the context menu and would display trading arrows in the chart to match the signals generated by the formula.

If we find that double-clicking is too much work, it is possible to mark Sync chart on select option in Analysis window settings menu:

Sync chart on select

and then single click to select a chart is enough to sync the symbol in the chart. This also allows to use keyboard (up/down cursor keys) to change the selection and sync automatically.

When we have more than one chart window displayed, then Analysis window will always sync the last opened chart window.

If we want to sync multiple chart windows we can use Symbol Link feature. Once multiple windows have the same “Symbol Link” color selected, browsing through the results list in Analysis automatically will automatically sync all linked chart windows (e.g. for the purpose of showing different intervals in each of the charts).

Linking

More information about chart link functionality is available in tutorials at:
http://www.amibroker.com/guide/h_sheets.html. See also video tutorial showing how to use symbol linking: http://www.amibroker.com/video/FloatAndLink.html

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