Scatterplot

The scatter plot can be used to overlay individual points (x, y) on top of an existing plot. Currently, the scatterplot cannot be the first plot on a subplot, it must be overlaid onto an existing plot.

The main use case of the scatter plot is to plot trade entry and exit points over a chart of prices.

In rallyplot, x-axis labels may be omitted (in which case the integer positions are used by default) or explicitly provided as an array of strings or UTC datetimes (see here for more details). When using the scatter plot, x-positions can be specified as integers (which always work), or as an array of strings or datetimes. If strings or datetimes are used, their types must match the x-axis label type already used in the chart.

Python

import numpy as np
from rallyplot import Plotter
from rallyplot import get_toy_candlestick_data

candle_df, _, dates = get_toy_candlestick_data(N=100_000)
prices = candle_df["open"].to_numpy()

plotter = Plotter(
    anti_aliasing_samples=8,
)

plotter.line(
    prices,
    dates=dates,
)

scatter_dates = np.ascontiguousarray(dates[::1000])
scatter_prices = np.ascontiguousarray(prices[::1000])

plotter.scatter(
    scatter_dates,
    scatter_prices,
    shape="cross",
    color=(0.5, 0.0, 0.5, 1.0),
)

plotter.start()

C++

#include <Plotter.h>
#include <ToyData.h>
#include <vector>

int main(int argc, char* argv[])
{
    CandleData candleData = getToyCandlestickData(100000);

    std::vector<float> prices;
    std::vector<std::chrono::system_clock::time_point> dates;

    for (int i = 0; i < 100; i++)
    {
        prices.push_back(candleData.open[i * 1000]);
        dates.push_back(candleData.dates[i * 1000]);
    }

    Plotter plotter = Plotter();

    plotter.line(
        candleData.open,
        candleData.dates
        );

    ScatterSettings scatterSettings;
    scatterSettings.shape = ScatterShape::cross;
    scatterSettings.color = {0.5, 0.0, 0.5, 1.0};

    plotter.scatter(
        dates,
        prices,
        scatterSettings
        );

    plotter.start();

}