Sparkline

Added in version 0.27.0

A widget that is used to visually represent numerical data.

• Focusable
• Container

Examples

Basic example

The example below illustrates the relationship between the data, its length, the width of the sparkline, and the number of bars displayed.

Tip

The sparkline data is split into equally-sized chunks. Each chunk is represented by a bar and the width of the sparkline dictates how many bars there are.

Outputsparkline_basic.pysparkline_basic.tcss

from textual.app import App, ComposeResult
from textual.widgets import Sparkline

data = [1, 2, 2, 1, 1, 4, 3, 1, 1, 8, 8, 2]  # (1)!


class SparklineBasicApp(App[None]):
    CSS_PATH = "sparkline_basic.tcss"

    def compose(self) -> ComposeResult:
        yield Sparkline(  # (2)!
            data,  # (3)!
            summary_function=max,  # (4)!
        )


app = SparklineBasicApp()
if __name__ == "__main__":
    app.run()

1. We have 12 data points.
2. This sparkline will have its width set to 3 via CSS.
3. The data (12 numbers) will be split across 3 bars, so 4 data points are associated with each bar.
4. Each bar will represent its largest value. The largest value of each chunk is 2, 4, and 8, respectively. That explains why the first bar is half the height of the second and the second bar is half the height of the third.

Screen {
    align: center middle;
}

Sparkline {
    width: 3;  /* (1)! */
    margin: 2;
}

1. By setting the width to 3 we get three buckets.

Different summary functions

The example below shows a sparkline widget with different summary functions. The summary function is what determines the height of each bar.

Outputsparkline.pysparkline.tcss

import random
from statistics import mean

from textual.app import App, ComposeResult
from textual.widgets import Sparkline

random.seed(73)
data = [random.expovariate(1 / 3) for _ in range(1000)]


class SparklineSummaryFunctionApp(App[None]):
    CSS_PATH = "sparkline.tcss"

    def compose(self) -> ComposeResult:
        yield Sparkline(data, summary_function=max)  # (1)!
        yield Sparkline(data, summary_function=mean)  # (2)!
        yield Sparkline(data, summary_function=min)  # (3)!


app = SparklineSummaryFunctionApp()
if __name__ == "__main__":
    app.run()

1. Each bar will show the largest value of that bucket.
2. Each bar will show the mean value of that bucket.
3. Each bar will show the smaller value of that bucket.

Sparkline {
    width: 100%;
    margin: 2;
}

Changing the colors

The example below shows how to use component classes to change the colors of the sparkline.

Outputsparkline_colors.pysparkline_colors.tcss

from math import sin

from textual.app import App, ComposeResult
from textual.widgets import Sparkline


class SparklineColorsApp(App[None]):
    CSS_PATH = "sparkline_colors.tcss"

    def compose(self) -> ComposeResult:
        nums = [abs(sin(x / 3.14)) for x in range(0, 360 * 6, 20)]
        yield Sparkline(nums, summary_function=max, id="fst")
        yield Sparkline(nums, summary_function=max, id="snd")
        yield Sparkline(nums, summary_function=max, id="trd")
        yield Sparkline(nums, summary_function=max, id="frt")
        yield Sparkline(nums, summary_function=max, id="fft")
        yield Sparkline(nums, summary_function=max, id="sxt")
        yield Sparkline(nums, summary_function=max, id="svt")
        yield Sparkline(nums, summary_function=max, id="egt")
        yield Sparkline(nums, summary_function=max, id="nnt")
        yield Sparkline(nums, summary_function=max, id="tnt")


app = SparklineColorsApp()
if __name__ == "__main__":
    app.run()

Sparkline {
    width: 100%;
    margin: 1;
}

#fst > .sparkline--max-color {
    color: $success;
}
#fst > .sparkline--min-color {
    color: $warning;
}

#snd > .sparkline--max-color {
    color: $warning;
}
#snd > .sparkline--min-color {
    color: $success;
}

#trd > .sparkline--max-color {
    color: $error;
}
#trd > .sparkline--min-color {
    color: $warning;
}

#frt > .sparkline--max-color {
    color: $warning;
}
#frt > .sparkline--min-color {
    color: $error;
}

#fft > .sparkline--max-color {
    color: $accent;
}
#fft > .sparkline--min-color {
    color: $accent 30%;
}

#sxt > .sparkline--max-color {
    color: $accent 30%;
}
#sxt > .sparkline--min-color {
    color: $accent;
}

#svt > .sparkline--max-color {
    color: $error;
}
#svt > .sparkline--min-color {
    color: $error 30%;
}

#egt > .sparkline--max-color {
    color: $error 30%;
}
#egt > .sparkline--min-color {
    color: $error;
}

#nnt > .sparkline--max-color {
    color: $success;
}
#nnt > .sparkline--min-color {
    color: $success 30%;
}

#tnt > .sparkline--max-color {
    color: $success 30%;
}
#tnt > .sparkline--min-color {
    color: $success;
}

Reactive Attributes

Name	Type	Default	Description
data	Sequence[float] | None	None	The data represented by the sparkline.
summary_function	Callable[[Sequence[float]], float]	max	The function that computes the height of each bar.

Messages

This widget posts no messages.

Bindings

This widget has no bindings.

Component Classes

The sparkline widget provides the following component classes:

Use these component classes to define the two colors that the sparkline interpolates to represent its numerical data.

Note

These two component classes are used exclusively for the color of the sparkline widget. Setting any style other than color will have no effect.

Class	Description
sparkline--max-color	The color used for the larger values in the data.
sparkline--min-color	The colour used for the smaller values in the data.

---

textual.widgets.Sparkline class

def __init__(
    self,
    data=None,
    *,
    summary_function=None,
    name=None,
    id=None,
    classes=None,
    disabled=False
):

Bases: Widget

A sparkline widget to display numerical data.

Parameters

Parameter	Default	Description
data Sequence[float] | None	None	The initial data to populate the sparkline with.
summary_function Callable[[Sequence[float]], float] | None	None	Summarizes bar values into a single value used to represent each bar.
name str | None	None	The name of the widget.
id str | None	None	The ID of the widget in the DOM.
classes str | None	None	The CSS classes for the widget.
disabled bool	False	Whether the widget is disabled or not.

COMPONENT_CLASSES class-attribute

COMPONENT_CLASSES: set[str] = {
    "sparkline--max-color",
    "sparkline--min-color",
}

Use these component classes to define the two colors that the sparkline interpolates to represent its numerical data.

Note

These two component classes are used exclusively for the color of the sparkline widget. Setting any style other than color will have no effect.

Class	Description
sparkline--max-color	The color used for the larger values in the data.
sparkline--min-color	The colour used for the smaller values in the data.

data class-attribute instance-attribute

data = data

The data that populates the sparkline.

summary_function class-attribute instance-attribute

summary_function = reactive[
    Callable[[Sequence[float]], float]
](_max_factory)

The function that computes the value that represents each bar.