working with list of list instead of dataframes

[Fougl]

Description

Hi, I am wondering how difficult it is to change the chart.set and chart.update and chart.update_from_tick to actually accept list of lists? Concatenating to a dataframe gets extremely costly, if dataframe is a bit larger, also for live trading, its concatenating the ticks and calculating continously, which is not optimal.

Code example

No response

Method of implementation

No response

[EsIstJosh]

You could adapt / mimic js_data() in utils.py to work with nested lists instead of dataframes. Take each candle/datapoint's values, create a dictionary like this, put them all into a list (or don't if it's to update the chart) then dump it into json.

LineData = {
	time: Time;
	value: number;
}

CandleData = {
	time: Time;
	high: number;
	low: number;
	close: number;
	open: number;
}

Then just modify the set/update methods in abstract.py to accept your data. Now for the live data, analyze the logic behind the update()/update_from_tick() methods carefully so you can implement your version correctly.

AbstractChart needs it's own implementation of the set/update methods, separate from the ones in SeriesCommon btw.