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chord
chord

chord

Mojo function 🡭

chord

fn def chord(df: DataFrame, from_categories: String, to_categories: String, values: String, ring_fraction: Float64 = 0.080000000000000002, theme: Theme = Theme(WHITE, Color(UInt8(30), UInt8(100), UInt8(180), UInt8(255)), Color(UInt8(80), UInt8(80), UInt8(80), UInt8(255)), Color(UInt8(225), UInt8(225), UInt8(225), UInt8(255)), Color(UInt8(40), UInt8(40), UInt8(40), UInt8(255)), SIMD(12), SIMD(3.5), SIMD(2), Int(60), Int(20), Int(20), Int(50), True, False, False, Color(UInt8(240), UInt8(240), UInt8(240), UInt8(255)), Int(3), Color(UInt8(60), UInt8(110), UInt8(200), UInt8(255)), Color(UInt8(235), UInt8(235), UInt8(235), UInt8(255)), Color(UInt8(220), UInt8(90), UInt8(40), UInt8(255)), ColorRamp(), ColorPalette(), SIMD(3), SIMD(15), True, SIMD(1), Int(0), False, Color(UInt8(200), UInt8(60), UInt8(60), UInt8(255)), Color(UInt8(224), UInt8(224), UInt8(224), UInt8(255)), Color(UInt8(120), UInt8(120), UInt8(120), UInt8(255)), Color(UInt8(100), UInt8(100), UInt8(100), UInt8(255)), Color(UInt8(230), UInt8(230), UInt8(230), UInt8(255)), Color(UInt8(255), UInt8(255), UInt8(255), UInt8(255)), UInt8(90), UInt8(160), False, False, SIMD(0), SIMD(18), SIMD(14), Color(UInt8(110), UInt8(110), UInt8(110), UInt8(255)), SIMD(14), Color(UInt8(150), UInt8(150), UInt8(150), UInt8(255)), Color(UInt8(224), UInt8(236), UInt8(246), UInt8(200)), Color(UInt8(255), UInt8(255), UInt8(255), UInt8(255)), True, False, False, True, AxisPosition.EDGE, AxisPosition.EDGE, String("sans-serif"), True, UInt8(90), Int(5), Int(4), Int(130), Int(14), Int(8), Int(14), Int(100), Int(8), SIMD(4), OutputFormat.SVG, Tooltips.AUTO, Missing.DRAW, String("(missing)"), Int(1000), False, LineStyle.SOLID, SIMD(1.5), LineStyle.SOLID, LegendPosition.RIGHT, XAxisLabelRotation.AUTO, TickFormat.AUTO, TickFormat.AUTO), width: Int = Int(640), height: Int = Int(420), title: String = "", subtitle: String = "", x_title: String = "", y_title: String = "") -> Chart[Chord]

chord() over named columns of a dataframe_mojo DataFrame (#743). Each argument names a column instead of holding the values.

See Plot.encode_frame() for how columns are read and what a column with missing values does.

Args:

  • df (DataFrame): The frame to read.
  • from_categories (String): The string column for this channel.
  • to_categories (String): The string column for this channel.
  • values (String): The numeric column for this channel.
  • ring_fraction (Float64): See the list overload.
  • theme (Theme): See the list overload.
  • width (Int): See the list overload.
  • height (Int): See the list overload.
  • title (String): See the list overload.
  • subtitle (String): See the list overload.
  • x_title (String): See the list overload.
  • y_title (String): See the list overload.

Returns:

Chart[Chord]: The finished chart – unrendered.

Raises:

Error: A named column is missing, has the wrong dtype for its channel, or has missing values.

fn def chord[dtype: DType](from_categories: List[String], to_categories: List[String], values: List[Scalar[dtype]], ring_fraction: Float64 = 0.080000000000000002, theme: Theme = Theme(WHITE, Color(UInt8(30), UInt8(100), UInt8(180), UInt8(255)), Color(UInt8(80), UInt8(80), UInt8(80), UInt8(255)), Color(UInt8(225), UInt8(225), UInt8(225), UInt8(255)), Color(UInt8(40), UInt8(40), UInt8(40), UInt8(255)), SIMD(12), SIMD(3.5), SIMD(2), Int(60), Int(20), Int(20), Int(50), True, False, False, Color(UInt8(240), UInt8(240), UInt8(240), UInt8(255)), Int(3), Color(UInt8(60), UInt8(110), UInt8(200), UInt8(255)), Color(UInt8(235), UInt8(235), UInt8(235), UInt8(255)), Color(UInt8(220), UInt8(90), UInt8(40), UInt8(255)), ColorRamp(), ColorPalette(), SIMD(3), SIMD(15), True, SIMD(1), Int(0), False, Color(UInt8(200), UInt8(60), UInt8(60), UInt8(255)), Color(UInt8(224), UInt8(224), UInt8(224), UInt8(255)), Color(UInt8(120), UInt8(120), UInt8(120), UInt8(255)), Color(UInt8(100), UInt8(100), UInt8(100), UInt8(255)), Color(UInt8(230), UInt8(230), UInt8(230), UInt8(255)), Color(UInt8(255), UInt8(255), UInt8(255), UInt8(255)), UInt8(90), UInt8(160), False, False, SIMD(0), SIMD(18), SIMD(14), Color(UInt8(110), UInt8(110), UInt8(110), UInt8(255)), SIMD(14), Color(UInt8(150), UInt8(150), UInt8(150), UInt8(255)), Color(UInt8(224), UInt8(236), UInt8(246), UInt8(200)), Color(UInt8(255), UInt8(255), UInt8(255), UInt8(255)), True, False, False, True, AxisPosition.EDGE, AxisPosition.EDGE, String("sans-serif"), True, UInt8(90), Int(5), Int(4), Int(130), Int(14), Int(8), Int(14), Int(100), Int(8), SIMD(4), OutputFormat.SVG, Tooltips.AUTO, Missing.DRAW, String("(missing)"), Int(1000), False, LineStyle.SOLID, SIMD(1.5), LineStyle.SOLID, LegendPosition.RIGHT, XAxisLabelRotation.AUTO, TickFormat.AUTO, TickFormat.AUTO), width: Int = Int(640), height: Int = Int(420), title: String = "", subtitle: String = "", x_title: String = "", y_title: String = "") -> Chart[Chord]

A chord diagram: nodes arranged around a circle with arcs between them sized by connection strength, for visualizing many-to-many relationships (flows, correlations, co-occurrences) that would be harder to scan as a matrix of numbers.

Mark.CHORD: ring sectors for every distinct node across from_categories/to_categories, connected by ribbons sized by values. See Plot.encode_chord() (plot.mojo) for the data shape.

Example:

from dataviz import chord
from dataviz import save
from dataviz import Theme

def main() raises:
    # Illustrative hours contributed between teams during one quarter.
    # Repeated teams reveal both hubs and smaller cross-team exchanges.
    var from_teams: List[String] = [
        "Product", "Product", "Platform", "Platform", "Data", "Data",
        "Sales", "Support", "Security", "Security", "Support", "Sales",
    ]
    var to_teams: List[String] = [
        "Platform", "Data", "Security", "Support", "Product", "Sales",
        "Product", "Platform", "Product", "Data", "Sales", "Support",
    ]
    var collaboration_hours: List[Int] = [
        180, 125, 150, 95, 110, 70, 135, 105, 80, 55, 65, 45,
    ]

    var c = chord(
        from_teams,
        to_teams,
        collaboration_hours,
        title="Illustrative Cross-Team Project Hours",
    )
    save(c, "docs/src/examples/out_chord.svg")

Parameters:

  • dtype (DType)

Args:

  • from_categories (List[String]): Each flow’s source node, one entry per row.
  • to_categories (List[String]): Each flow’s destination node, one entry per row (paired with from_categories[i]).
  • values (List[Scalar[dtype]]): Each flow’s magnitude, sizing its ribbon; must be non-negative.
  • ring_fraction (Float64): The node rim’s thickness as a fraction of the circle radius; defaults to 0.08.
  • theme (Theme): Full styling knobs beyond this function’s own parameters (colors, margins, fonts, gridlines, …) – see Theme’s docstring.
  • width (Int): Pixel width of the returned Plot (.size()).
  • height (Int): Pixel height of the returned Plot (.size()).
  • title (String): The chart’s title, shown above the plot.
  • subtitle (String): A secondary line shown under the title.
  • x_title (String): The x-axis caption.
  • y_title (String): The y-axis caption.

Returns:

Chart[Chord]: The finished chart – unrendered. Call save(plot, path) to write it (any of .svg/.png/.bmp), or render(plot)/render_svg(plot) for the explicit two-step.

Raises: