Draw a rectangle every 30 minutes which encompasses candles

[jkosnikowski]

Hi,

I'm just learning so bear with me and if I'm headed in the wrong direction let me know.

I'm trying to draw a rectangle ever 30min that encompasses the candles in that 30min range. I would like to see a rectangle at 7:00 which goes till 7:30 at which a new rectangle is drawn and so on.

I've got code that is using OnBarUpdate() and I can successfully draw a dot every 30 minutes using the following which seems to be working great.

if(Time[0].Minute % 30 == 0)
{
Draw.Dot(this, "YourDot"+CurrentBar, true, 0, Low[0] - TickSize, Brushes.Red);
}

I understand I'll need to use MIN and MAX to find the High and Low over the bars/candles inside the 30min range. How do I go from the above Draw.Dot code to getting my rectangles to draw every 30min?

I've read that drawing rectangles can take a startTime and an endTime. I just don't understand how to get those values into the drawing code:

Draw.Rectangle(this, tagA, startTime, maxLow, endTime, maxHigh, Brushes.Cyan);

Do I need to use some kind of looping inside my code above?

Any hints, suggestions or guidance would be welcome and thank you in advance.

[NinjaTrader_ChelseaB]

Hello jkosnikowski,

The rectangle will need a start bar and an end bar.

The start bar would be 30 minutes previous to the current bar, which can be found with Bars.GetBar(Time[0].AddMinutes(-30)).

Subtract this from CurrentBar and this would give you a barsAgo number (for how many bars ago 30 minutes was).

This can then be used to get the MAX or MIN of that many bars.

int barsAgoValue = CurrentBar - Bars.GetBar(Time[0].AddMinutes(-30));

Print(MAX(High, barsAgoValue)[0]);

[jkosnikowski]

Chelsea B,

Thank you so much for the reply. I managed to get this working and it's perfect.
For anyone doing something similar I ended up with the following.

if(Time[0].Minute % 30 == 0)
{
//Draw a red dot as a test
Draw.Dot(this, "YourDot"+CurrentBar, true, 0, Low[0] - TickSize, Brushes.Red);

//Rectangles
int barsAgoValue = CurrentBar - Bars.GetBar(Time[0].AddMinutes(-30));
double barMax = (MAX(High, barsAgoValue)[0]);
double barMin = (MIN(Low, barsAgoValue)[0]);
Draw.Rectangle(this, "tagAA"+CurrentBar, 0, barMin, barsAgoValue, barMax, Brushes.Cyan);
}

It does however have the issues of giving an error that the value of "Period" "MAX" is 0 and not in the valid range. I must be missing something else