PercentRank Function for AmiBroker

Friend of the blog, Ramon Cummins has graciously agreed to share his PercentRank function for AmiBroker language. This is a really useful function. It returns the rank of a value in a set of values as a percentage of the set. In other words, if an indicator produces a raw value, this function allows one to rank the raw value as a percentage of previous values.

//PercentRank Function
//As Coded by Ramon Cummins
function PercentRank( Data, Periods )
{
Count = 0;
for ( i = 1; i < Periods + 1 ; i++ )
{
Count = Count + IIf ( Ref( Data, 0 ) > Ref( Data, -i ), 1, 0 );
}
return 100 * Count / Periods;
}

//Now, lets use the function to rank  Average True Range in percentage terms relative to previous ATRs.
//Define ATR as a percentage
ATR_Percentage=(ATR(10)/C)*100;
//Here we define the lookback period (30 days) to compare current to previous ATR%
RankPeriods = Param( “PercentRank Lookback Periods”, 30,5,252,5 );
//Here we use the PercentRank function to rank the ATR% relative to previous ATR%s
ATR_Bounded = PercentRank( ATR_Percentage, RankPeriods );
if ( ParamToggle( “Show ATR_Bounded”, “No|Yes”, 1 ) == 1  )
{
Plot( ATR_Bounded, _DEFAULT_NAME(), ParamColor( “Color”, colorCycle ), ParamStyle( “Style” ) );
}

And below is a screenshot showing the ATR_Bounded applied to the Qs.