Explain what this is useful for?

[maslowski95]

def lastBar = HighestAll(if !IsNaN(close) then BarNumber() else 0);

A script was handed to me by a client and they had this line in their script. I've seen HighestAll(BarNumber()) before I'm just unsure what this value is actually holding.

They go on to use this variable in calculations later, such as:

def offset = Min(waveLength - 1, lastBar - BarNumber());

Doesn't Highest all calculate the highest value within a range, feeding it BarNumber would give up until the current time? Why assign this to 'last bar'?

 

[Joshua]

Each bar is incrementally numbered from left to right. In this particular case, HighestAll will return the number of the final bar on the chart, while avoiding any potential blank bars, which are created by the right side expansion area in the time axis settings. Its forward looking.

lastBar - BarNumber() would give the number of bars remaining on each iteration of the script.

I am assuming waveLength is the number of bars to use in some other calculation.

Using Min() to get the smaller of the two, I am assuming, is used so that waveLength does not overrun the available data as it runs out on the right edge of the chart.

I should note that HighestAll(), along will all full range functions, were changed a little while back. Their inclusion will now force a ONCE_PER_BAR declaration without consent.

 

[maslowski95]

Each bar is incrementally numbered from left to right. In this particular case, HighestAll will return the number of the final bar on the chart, while avoiding any potential blank bars, which are created by the right side expansion area in the time axis settings. Its forward looking.

lastBar - BarNumber() would give the number of bars remaining on each iteration of the script.

I am assuming waveLength is the number of bars to use in some other calculation.

Using Min() to get the smaller of the two, I am assuming, is used so that waveLength does not overrun the available data as it runs out on the right edge of the chart.

I should note that HighestAll(), along will all full range functions, were changed a little while back. Their inclusion will now force a ONCE_PER_BAR declaration without consent.

so lastBar - BarNumber() will always be zero or less, no? This means they are basically asking is (12 - Znonpos) which will 100% always evaluate to true. I'm sorry I'm very unfamiliar with ThinkScript and just getting my bearings. Wavelength is =13 so that's why I say in the example it's always 12.

 

[Joshua]

Zero or more, lastbar will be the bar number of the right most bar. BarNumber() will be the number of the current bar as the script iterates though each bar from left to right.

10 bars total, on bar 8 = 2 bars remaining.

If 2 < wavelength, then just use 2 instead of wavelength, or else you get into NaN values or something.

There is very likely an easier way to do this without highest all as well