You post code which says you are doing this:

@emmepra said in Plot BuySell Observer with Tick Data:

cerebro = bt.Cerebro(stdstats=False)
cerebro.addobserver(bt.observers.BuySell)

But the chart shows you are NOT doing that, because the observer has the following legend: BuySellObserver(True, 0), where True is the value for the parameter barplotdist, which has a default value of False. Furthermore, the parameter bardist has a default value of 0.015 (i.e.: 1%) but the chart shows it to be 0.

Two parameters have changed its default value as shown in the chart, but the code which supposedly doesn't work doesn't change anything.

You may actually want to try with the code you show (I never tried it with ticks ... it may or it may not work)

Use the len of the data to know how many items are available.

@t3chap said in How to build a sizer that can use some measure of volatility, like ATR, and the multiplier for the future to determine position sizing?:

I seem to have a position size of 0 for every trade.

With the following code ...

@t3chap said in How to build a sizer that can use some measure of volatility, like ATR, and the multiplier for the future to determine position sizing?:

class comm_sizer(bt.Sizer):
    def __init__(self, atr):
        #self.atr_parameter= atr_parameter
        atr= self.atr
        risk_per_trade=5000
        atr_risk_per_trade=5
        
        sizing = math.floor((risk_per_trade/(mult*atr_risk_per_trade*atr)))
        
   # position = self.broker.getposition(data)
    
    def _getsizing(self,comminfo,cash,data,isbuy):
        
        return sizing

It would be a miracle if you get something other than an Exception, both in __init__ and in _getsizing.

In any case to use the ATR you probably want to access the strategy attributes (where the ATR will have been instantiated), taking advantage of the fact that the sizers have an attribute member called strategy

• https://www.backtrader.com/docu/sizers/sizers/

Dear @P-dML ,

For sure your explanation makes sense to you, because you are deep into your problem. But as pointed out by @run-out in the question ... without code there is actually no way to know what you are doing. For example:

• There is a getsizing(data) thrown into a sentence out of the blue ...

At least for me it is unclear why that isn't giving you the information you are missing, probably because I also don't know which data feeds are in the equation, what's being targeted, ...

@Bayne said in Memory Error Plotting (Ticks):

Data is not more than 2 weeks, but even need more.

Buy a PC with more memory and you will be able to plot more (OS may impose limits on memory allocation)

@Bayne said in Memory Error Plotting (Ticks):

Is it possible to plot it in Upsampled Bars, to save memory?

It will obviously use less room. But you won't see the ticks.

@Bayne said in Does it pay off (in accuracy terms) to load lower TimeFrame Data?:

Do upsampled bars Take into consideration the smaller moves in between (which are Not OHLC) for executing Orders or not?

You obviously don't now what upsampling (known as resampling) means. Smaller moves cannot be taken into account because the information is lost. You compress (with information loss) n-bars into 1-bar.

You may use use the resampled data to trigger signals and target the lower timeframe for execution. Or use replay: https://www.backtrader.com/docu/data-replay/data-replay/

You can always use the non-adjusted close and see how your strategy fares when a 5x1 split happens.

You are for sure NOT doing that.

@emmepra said in Plot BuySell Observer with Tick Data:

cerebro = bt.Cerebro(stdstats=False)
cerebro.addobserver(bt.observers.BuySell)

If you were the observer wouldn't say ... BuySell(True, 0). That's the problem with redacted non-working code, it is usually not the code actually executing.

See: https://www.backtrader.com/docu/observers-reference/

@jesseliu0 said in How to disable plotting data?:

only plot observers and analyzers?

analyzers are not plotted in any instance.

It is unclear from your message what happens when you run the code.

What do you have to contribute?