Exporting charts¶

Export a chart by rendering it to image bytes with chart.render(fmt), then write the bytes wherever they need to go — a file, a web page, an HTTP response. Supported formats include SVG, PNG, and JPG.

In [6]:

from mplchart.chart import Chart
from mplchart.samples import sample_prices
from mplchart.primitives import Candlesticks, Volume, Pane, Line
from mplchart.indicators import SMA, RSI, MACD

prices = sample_prices()

from mplchart.chart import Chart from mplchart.samples import sample_prices from mplchart.primitives import Candlesticks, Volume, Pane, Line from mplchart.indicators import SMA, RSI, MACD prices = sample_prices()

Plot chart with indicators¶

In [7]:

max_bars = 250

chart = Chart(prices, title="Example", max_bars=max_bars).plot(
    Candlesticks(),
    SMA(50),
    SMA(200),
    Volume(),
    Pane("above", yticks=(30, 50, 70)),
    Line(RSI(), overbought=70, oversold=30),
    Pane("below"),
    MACD(),
)

max_bars = 250 chart = Chart(prices, title="Example", max_bars=max_bars).plot( Candlesticks(), SMA(50), SMA(200), Volume(), Pane("above", yticks=(30, 50, 70)), Line(RSI(), overbought=70, oversold=30), Pane("below"), MACD(), )

Render to SVG or PNG¶

In [8]:

data = chart.render("svg")

print(data[:20] + b"...")

data = chart.render("svg") print(data[:20] + b"...")

b'<?xml version="1.0" ...'

In [9]:

data = chart.render("png")

print(data[:20] + b"...")

data = chart.render("png") print(data[:20] + b"...")

b'\x89PNG\r\n\x1a\n\x00\x00\x00\rIHDR\x00\x00\x04\xb0...'

Saving to a file¶

render returns bytes and deliberately stops there — writing them is one line with whatever destination you have:

from pathlib import Path

Path("chart.svg").write_bytes(chart.render("svg"))
Path("chart.png").write_bytes(chart.render("png"))

The same bytes embed directly in a web response or an HTML <img> tag — see the Chart.render entry in the API reference for the format and dpi options.