drawlib.charts.radar

2D multivariate radar (spider web) chart builder evaluating three or more radial dimensions across polygon or circular concentric grids. Import from drawlib.charts.radar (from drawlib.charts.radar import GridShape, RadarChart, Series).

15_charts_radar_1
Polygon Web and Circular Concentric Grid RadarChart Layouts
Source Code 
from drawlib.canvas import save, setup
from drawlib.charts.radar import RadarChart
from drawlib.shapes import rectangle
from drawlib.styles import Colors, Styles

setup(width=120, height=62)

card_style = Styles.Neutral.patch(shape_r=2.0, shape_line_color=Colors.Gray4, shape_fill_color=Colors.White)
rectangle((31.5, 31.0), width=53.0, height=54.0, style=card_style)
rectangle((88.5, 31.0), width=53.0, height=54.0, style=card_style)

# Left: Polygon Grid RadarChart
poly = RadarChart(
    categories=["Scale", "Speed", "Sec", "UX", "SLA"],
    axis_line_style=Styles.MutedDashed,
    axis_text_style=Styles.BlackBold.patch(text_size=10.0),
    grid_style=Styles.MutedThin,
    radius=11.5,
    width=48.0,
    height=40.0,
    min_value=0.0,
    max_value=100.0,
    levels=4,
    grid_shape="polygon",
    title="Polygon Trade-off Web",
    title_style=Styles.BlackBold.patch(text_size=11.5),
)
poly.add_series("Target", [70.0, 85.0, 75.0, 85.0, 78.0], style=Styles.SecondaryNeutral, fill_alpha=0.25, line_style="dashed")
poly.add_series("Actual", [92.0, 78.0, 90.0, 76.0, 95.0], style=Styles.PrimaryFlat, fill_alpha=0.28)
poly.draw(xy=(7.5, 14.0))
poly.draw_legend(xy=(17.5, 8.5), text_style=Styles.DarkBold.patch(text_size=10.0), orientation="horizontal")

# Right: Circular Grid RadarChart
circ = RadarChart(
    categories=["API", "Docs", "Perf", "Test", "Ops", "Cost"],
    axis_line_style=Styles.MutedDashed,
    axis_text_style=Styles.BlackBold.patch(text_size=10.0),
    grid_style=Styles.MutedThin,
    scale_text_style=Styles.Muted.patch(text_size=10.0),
    radius=11.5,
    width=48.0,
    height=40.0,
    levels=2,
    grid_shape="circle",
    title="Circular Benchmark Grid",
    title_style=Styles.BlackBold.patch(text_size=11.5),
)
circ.configure_axis(min_value=0.0, max_value=10.0, levels=2, scale_format="{:.0f}")
circ.add_series("v1", [6.8, 7.0, 7.5, 8.0, 7.0, 8.5], style=Styles.SecondaryNeutral, line_style="dashed", point_shape="none")
circ.add_series("v2", [7.8, 9.0, 9.4, 9.0, 8.8, 7.8], style=Styles.PrimaryFlat, point_size=0.65)
circ.draw(xy=(64.5, 14.0))
circ.draw_legend(xy=(79.5, 8.5), text_style=Styles.DarkBold.patch(text_size=10.0), orientation="horizontal")

save()

typeDrawDirection#

Spatial partial-rendering direction used with Series.draw_ratio (0.0 to 1.0) for progressive radar polygon animations.

DrawDirection = Literal["bottom_to_top", "left_to_right"]
Literal Value RadarChart Behavior
"bottom_to_top" Expands all spoke vertices radially outward simultaneously from min_value at the center origin (default).
"left_to_right" Sweeps the closed polygon spoke-by-spoke around the perimeter from spoke 0 to N - 1.

typeFormatterType#

Union type controlling numeric formatting for concentric scale rings (scale_format) and series vertex labels (value_format).

FormatterType = str | Callable[[float], str] | None
  • str: Python format string (e.g. "{:.0f}", "{:.1f}").
  • Callable[[float], str]: Custom formatter callable mapping a numeric float to a display string.
  • None: Automatic compact numeric formatting.

typeGridShape#

Literal type specifying the geometry of concentric scale rings (RadarChart.grid_shape).

GridShape = Literal["polygon", "circle"]
Literal Value Description
"polygon" Connects spoke tick marks with straight polygonal web segments (default).
"circle" Renders smooth concentric circular rings across radial spokes.

typeLegendPosition#

Literal type representing preset legend placement identifiers.

LegendPosition = Literal["top", "bottom", "right", "none", "auto"]

classRadarChart#

2D radar (spider web) chart builder evaluating multivariate entities across three or more symmetric radial spokes emanating from a central origin.

  • Coordinate Anchor: Bottom-Left (x0, y0) by default in draw(xy=..., align="bottom_left"), or geometric center when align="center".
  • Minimum Spokes: Requires len(categories) >= 3 to form a closed radial polygon (passing fewer raises a ValueError).
class RadarChart:
    def __init__(
        self,
        *,
        categories: list[str],
        axis_line_style: Style,
        radius: float = 25.0,
        min_value: float = 0.0,
        max_value: float | None = None,
        levels: int = 5,
        grid_shape: GridShape = "polygon",
        axis_text_style: Style | None = None,
        grid_style: Style | None = None,
        scale_text_style: Style | None = None,
        scale_format: FormatterType = None,
        value_text_style: Style | None = None,
        value_format: FormatterType = None,
        background_style: Style | None = None,
        title: str = "",
        title_style: Style | None = None,
        width: float | None = None,
        height: float | None = None,
    ) -> None: ...

Parameters#

Parameter Type Default Description
categories list[str] Required Names of radial dimensions around the perimeter (minimum 3 required).
axis_line_style Style Required Mandatory style for the radial spoke axis lines.
radius float 25.0 Outer radius of the radar web in canvas units.
min_value float 0.0 Baseline data value mapped to the central origin point.
max_value float | None None Outer ring scale value. Auto-computed from series values when None.
levels int 5 Number of concentric grid contours (minimum 1).
grid_shape GridShape "polygon" Concentric gridline geometry ("polygon" or "circle").
axis_text_style Style | None None Style for outer perimeter dimension category labels. Omitted when None.
grid_style Style | None None Style for concentric grid contours. Omitted when None.
scale_text_style Style | None None Style for numeric scale labels along the top vertical spoke. Omitted when None.
scale_format FormatterType None Format string or callable for concentric ring scale values.
value_text_style Style | None None Style for numeric values drawn next to series vertices. Omitted when None.
value_format FormatterType None Format string or callable for series vertex values.
background_style Style | None None Outer chart background card style. Omitted when None.
title str "" Chart title text displayed at the top of the container.
title_style Style | None None Typography style required to render title. Omitted when None.
width float | None None Explicit container width override. Computed from radius and title when None.
height float | None None Explicit container height override. Computed from radius and title when None.

Methods & Properties#

add_series

def add_series(
    self,
    name: str,
    values: list[float],
    style: Style,
    fill_alpha: float = 0.25,
    line_width: float = 2.0,
    line_style: LineStyle = "solid",
    point_shape: PointShape = "circle",
    point_size: float = 0.8,
    legend_text_style: Style | None = None,
    *,
    show: bool = True,
    draw_ratio: float = 1.0,
    draw_direction: DrawDirection = "bottom_to_top",
) -> Series

Adds a closed radar polygon series and returns the mutable Series instance (values length must match len(categories); pass point_shape="none" to hide vertex markers).

categories *(property)*

@property
def categories(self) -> list[str]

Returns a list copy of the radial dimension labels.

configure_axis

def configure_axis(
    self,
    *,
    min_value: float | None = None,
    max_value: float | None = None,
    levels: int | None = None,
    scale_format: FormatterType = None,
) -> RadarChart

Updates radial scale bounds, concentric contour ring count, and scale label formatting in place, returning self for method chaining.

draw

def draw(
    self,
    xy: tuple[float, float] = (0.0, 0.0),
    *,
    radius: float | None = None,
    width: float | None = None,
    height: float | None = None,
    align: Literal["bottom_left", "center"] = "bottom_left",
    scale: float = 1.0,
) -> None

Renders the radar chart onto the canvas anchored at xy (Bottom-Left (x0, y0) by default, or geometric center when align="center"), with optional one-call radius, width, height, and scale overrides.

draw_legend

def draw_legend(
    self,
    xy: tuple[float, float],
    text_style: Style,
    orientation: Literal["vertical", "horizontal"] = "vertical",
    swatch_width: float = 2.4,
    swatch_height: float = 1.2,
    item_gap: float = 4.0,
    *,
    scale: float = 1.0,
) -> None

Renders a standalone series legend at xy ("vertical" or "horizontal").

get_size

def get_size(self) -> tuple[float, float]

Computes and returns the total (width, height) bounding box dimensions of the radial chart container.

series *(property)*

@property
def series(self) -> list[Series]

Returns a list copy of registered Series instances.

classSeries#

Mutable data model representing a closed radar polygon series in a RadarChart.

class Series:
    def __init__(
        self,
        name: str,
        values: list[float],
        style: Style,
        fill_alpha: float = 0.25,
        line_width: float = 2.0,
        line_style: LineStyle = "solid",
        point_shape: PointShape = "circle",
        point_size: float = 0.8,
        legend_text_style: Style | None = None,
        show: bool = True,
        draw_ratio: float = 1.0,
        draw_direction: DrawDirection = "bottom_to_top",
    ) -> None: ...

Parameters & Attributes#

Parameter / Attribute Type Default Description
name str Required Series display name shown in draw_legend().
values list[float] Required Numeric values aligned with RadarChart.categories.
style Style Required Polygon fill, perimeter stroke, and vertex marker Style.
fill_alpha float 0.25 Opacity (0.0 to 1.0) of the interior polygon fill.
line_width float 2.0 Perimeter stroke width.
line_style "solid" | "dashed" | "dotted" | "dashdot" "solid" Perimeter stroke dash pattern.
point_shape "circle" | "square" | "rhombus" | "triangle" | "none" "circle" Marker geometry drawn at each spoke vertex ("none" hides markers).
point_size float 0.8 Vertex marker radius in canvas units.
legend_text_style Style | None None Optional custom text style for this series in draw_legend().
show bool True Toggles polygon visibility while preserving automatic max_value scaling.
draw_ratio float 1.0 Spatial rendering progress (0.0 to 1.0) for animations.
draw_direction DrawDirection "bottom_to_top" Partial rendering direction ("bottom_to_top" radial expansion or "left_to_right" spoke sweep).