Chord diagram

A chord diagram template. Lets you visualise connections between two entities.

Updated 3 years ago to v5.1.0 by Flourish team

How to use this template

This template is useful for showing relationships and the flow to and from values. It gives the option to color the chords as linear gradients or have the chords filled based on the source which is determined by the bigger flow.

Data requirements

There must be three columns. The first specifies the values from, the second specifies the values to, and the third is the count (a numerical number describing how many flows there were).

Tips

  • You can change the color based on your needs. By default it is a gradient but you can also use a fill colour. The fill colour is based on the biggest value.

  • If your text label is overlapping and your label alignment is "Along Arcs" your overlapping text label will not show up. This might be convenient for you, but you can also flip the label 90° that way your label won't overlap and will show up.

  • Chord diagrams can be difficult to understand so make sure to add an appropriate title. You can also add a popup to make it easier for the user to understand.

  • Flourish allows you to export an SVG. Do this if you want to add annotations in your favourite vector editing program.

Credits

Created by the Flourish team. Sample data from Crazy for Friends. Want to see additional features? Let us know at support@flourish.studio.

This section documents API usage specific to this template, so for an introduction we suggest you refer to the generic API documentation instead.

template: @flourish/chord-diagram

version: 5

Template data

There are three different formats in which you can supply data to this template. The most convenient for you to use likely depends on the source of your data, as described below.

1. Array of arrays, and a bindings object

You can supply arrays of arrays to opts.data, which might look like:

{
    data: {
        connections: [
            [ "ConnectionsColumn1Value1", "ConnectionsColumn2Value1",
            [ "ConnectionsColumn1Value2", "ConnectionsColumn2Value2",
            [ "ConnectionsColumn1Value3", "ConnectionsColumn2Value3",
            ...
        ]
    }
}

where each array of arrays represents the rows in a data sheet.

To tell the API how the values from each column should be associated with the keys that the template is expecting, you must also supply an object attached to opts.bindings. (The meanings of the keys in the bindings object are documented below.) The minimal bindings you can supply for this template are as shown in this example:

{
    template: "@flourish/chord-diagram",
    version: "5",
    bindings: {
        connections: {
            from: 0, // index of a column in your data
            to: 1, // index of a column in your data
            value: 2, // index of a column in your data
        }
    },
    data: {
        connections: [
            [ "ConnectionsColumn1Value1", "ConnectionsColumn2Value1",
            [ "ConnectionsColumn1Value2", "ConnectionsColumn2Value2",
            [ "ConnectionsColumn1Value3", "ConnectionsColumn2Value3",
            ...
        ]
    }
}

All possible bindings that you can supply are shown in this example:

{
    template: "@flourish/chord-diagram",
    version: "5",
    bindings: {
        connections: {
            from: 0, // index of a column in your data
            to: 1, // index of a column in your data
            value: 2, // index of a column in your data
        }
    },
    data: {
        connections: [
            [ "ConnectionsColumn1Value1", "ConnectionsColumn2Value1",
            [ "ConnectionsColumn1Value2", "ConnectionsColumn2Value2",
            [ "ConnectionsColumn1Value3", "ConnectionsColumn2Value3",
            ...
        ]
    }
}

2. Array of objects with arbitrary keys, and a bindings object

This format is most likely useful when you have data from an external source, such as CSV data loaded from d3-dsv. You should supply this attached to the opts.data, which might look like:

{
        connections: [
            { "ConnectionsHeader1": ..., "ConnectionsHeader2": ..., ... },
            { "ConnectionsHeader1": ..., "ConnectionsHeader2": ..., ... },
            { "ConnectionsHeader1": ..., "ConnectionsHeader2": ..., ... },
            ...
        ]
    }

... but with the keys being the column headers from your source data instead. You must also supply an object attached to opts.bindings. The minimal bindings you can supply for this template are as shown in this example:

{
    template: "@flourish/chord-diagram",
    version: "5",
    bindings: {
        connections: {
            from: "ConnectionsHeader1",
            to: "ConnectionsHeader2",
            value: "ConnectionsHeader3",
        }
    },
    data: {
        connections: [
            { "ConnectionsHeader1": ..., "ConnectionsHeader2": ..., ... },
            { "ConnectionsHeader1": ..., "ConnectionsHeader2": ..., ... },
            { "ConnectionsHeader1": ..., "ConnectionsHeader2": ..., ... },
            ...
        ]
    }
}

All possible bindings that you can supply are shown in this example:

{
    template: "@flourish/chord-diagram",
    version: "5",
    bindings: {
        connections: {
            from: "ConnectionsHeader1",
            to: "ConnectionsHeader2",
            value: "ConnectionsHeader3",
        }
    },
    data: {
        connections: [
            { "ConnectionsHeader1": ..., "ConnectionsHeader2": ..., ... },
            { "ConnectionsHeader1": ..., "ConnectionsHeader2": ..., ... },
            { "ConnectionsHeader1": ..., "ConnectionsHeader2": ..., ... },
            ...
        ]
    }
}

(As before, the keys containing "Header" would be replaced by column names from your data source.)

3. Array of objects with template-defined keys

There is an alternative format you can use, which is likely to be easier to use if your data is not from a spreadsheet source. With this alternative format you supply your data to the template as an array of objects, attached to opts.data, where the keys must be those used by the template, as documented below. In this case there is no need to supply a bindings object, since the key names are already those expected by the template. The required properties in the data object are as follows (scroll down for a description of what each property is):

{
    template: "@flourish/chord-diagram",
    version: "5",
    data: {
    connections: [
        {
            from: ...,
            to: ...,
            value: ...
        },
        ...
    ]
},
    ...
}

And the full list of all possible properties is as follows:

{
    template: "@flourish/chord-diagram",
    version: "5",
    data: {
    connections: [
        {
            from: ...,
            to: ...,
            value: ...
        },
        ...
    ]
},
    ...
}

Meanings of the template data keys:

  • connections.from: from
  • connections.to: to
  • connections.value: A number specifying the size of the flow

Template settings

Options for opts.state.

Colour

color.scale_type string

Scale type.

Allowed values:

  • categorical (Categorical)
  • numeric (Numeric)

color.categorical_palette colors

Palette.

color.categorical_extend boolean

Extend. Automatically generate additional colours when needed to avoid the palette colours being used more than once.

color.categorical_custom_palette text

Custom overrides. Type the name of the entity whose colour you want to set, a colon and then a colour (using a name, hex-code or rgb declaration). Multiple colours can be set using multiple lines. For example:<br /><hr />Party 1: red<br />Party 2: #4455AA<br />Party 3: rgb(30,168,26)

color.numeric_type string

Scale type.

Allowed values:

  • sequential (Sequential)
  • diverging (Diverging)

color.binning boolean

In linear mode, the color scale will run as a smooth gradient between 2 colors. In binned mode, the gradient will be divided in smaller blocks.

Allowed values:

  • false (Linear)
  • true (Binned)

color.bin_mode string

Binning mode.

Allowed values:

  • fixed (Fixed width)
  • quantile (Quantile)
  • custom (Custom thresholds)

color.bin_count number

Number of bins.

color.bin_thresholds string

Custom thresholds. Write your custom thresholds, separated by a ";" For example 5;10;15

color.sequential_palette string

Palette.

Allowed values:

  • Oranges
  • Reds
  • Blues
  • Greens
  • Greys
  • Purples
  • Viridis
  • Inferno
  • Magma
  • Plasma
  • Warm
  • Cool
  • CubehelixDefault (Cubehelix)
  • BuGn (Blue/Green)
  • BuPu (Blue/Purple)
  • GnBu (Green/Blue)
  • OrRd (Orange/Red)
  • PuBuGn (Purple/Blue/Green)
  • PuBu (Purple/Blue)
  • PuRd (Purple/Red)
  • RdPu (Red/Purple)
  • YlGnBu (Yellow/Blue/Green)
  • YlGn (Yellow/Green)
  • YlOrBr (Yellow/Orange/Brown)
  • YlOrRd (Yellow/Orange/Red)
  • Carrots
  • Custom

color.sequential_reverse boolean

Reverse.

color.sequential_custom_min color

Minimum color.

color.sequential_custom_max color

Maximum color.

color.sequential_color_space string

Color space.

Allowed values:

  • rgb (RGB)
  • lab (LAB)
  • hcl (HCL)
  • hsl (HSL)

color.sequential_custom_domain boolean

Domain.

Allowed values:

  • false (Auto)
  • true (Custom)

color.sequential_domain_min number

Min.

color.sequential_domain_max number

Max.

color.diverging_palette string

Palette.

Allowed values:

  • RdBu (Red/Blue)
  • RdYlGn (Red/Yellow/Green)
  • PiYG (Pink/Yellow/Green)
  • BrBG (Brown/Blue/Green)
  • PRGn (Purple/Red/Green)
  • PuOr (Purple/Orange)
  • RdGy (Red/Grey)
  • RdYlBu (Red/Yellow/Blue)
  • Spectral
  • Custom

color.diverging_reverse boolean

Reverse.

color.diverging_custom_min color

Minimum color.

color.diverging_custom_mid color

Midpoint color.

color.diverging_custom_max color

Maximum color.

color.diverging_color_space string

Color space.

Allowed values:

  • rgb (RGB)
  • lab (LAB)
  • hcl (HCL)
  • hsl (HSL)

color.diverging_custom_domain boolean

Domain.

Allowed values:

  • false (Auto)
  • true (Custom)

color.diverging_domain_min number

Min.

color.diverging_domain_mid number

Mid.

color.diverging_domain_max number

Max.

gradient_type string

Chord colour mode.

Allowed values:

  • linear_gradient (Gradient)
  • largest_end (Larger end)
  • smallest_end (Smaller end)

Chords

opacity_chord number

Chord Opacity.

Max: 1

selected_chords text

Highlight chords. To highlight an chords ribbons, write the name of each arc on a line. You can also create a story and highlight/unhighlight by clicking.

use_mouseover_label boolean

Show chord values on hover.

show_selected_label boolean

Keep chord values on click.

chord_labels_reponsive boolean

Label text size. Auto changed the label size based on the window size, subject to the specified min and max

Allowed values:

  • true (Auto)
  • false (Fixed)

chord_label_font_size number

Text size.

Max: 4

chord_label_font_size_min number

Min size.

Max: 4

chord_label_font_size_max number

Max size.

Max: 4

show_chord_stroke boolean

Allowed values:

  • true (Enabled)
  • false (Disabled)

chord_stroke_color color

Stroke color.

chord_stroke_opacity number

Stroke opacity.

Max: 1

Arcs

arc_thickness number

Thickness. As a percentage of the radius

Max: 80

arc_spacing number

Gap below. As a percentage of the radius

Max: 40

pad_angle number

Gap between. in degrees

Max: 180

label_alignment string

Alignment.

Allowed values:

  • along_arcs (Along Arcs)
  • 90_rotated (90° rotated)

label_responsive boolean

Label text size. Auto changed the label size based on the window size, subject to the specified min and max

Allowed values:

  • true (Auto)
  • false (Fixed)

label_font_size number

Text size.

Max: 4

label_font_size_min number

Min size.

Max: 4

label_font_size_max number

Max size.

Max: 4

label_color color

Arc label color.

use_label_color_arc boolean

Make the arc label color the same as the arc color.

popup.show_popups boolean

Popups.

Allowed values:

  • true (Enabled)
  • false (Disabled)

popup.is_custom boolean

Popup contents.

Allowed values:

  • false (Auto)
  • true (Custom content)

popup.custom_template text

Popup content. The text to appear in the popup. You can use {{column_name}} to add a value from your data. It must be in a selected column, but you can add columns to “Metadata” if you just want to include them for use in the popup. Advanced users can include HTML to apply layouts, formatting, images, etc.

popup.show_pointer boolean

Pointer.

popup.show_shadow boolean

Shadow.

popup.style_popups boolean

Custom styling.

popup.text_color color

Text colour.

popup.align string

Alignment.

Allowed values:

  • left (fa-align-left)
  • center (fa-align-center)
  • right (fa-align-right)

popup.font_size number

Font size.

Min: 1

popup.fill_color color

Fill colour.

popup.opacity number

Fill opacity.

Max: 1

popup.padding number

Padding.

popup.border_radius number

Radius. Corner radius of popup

Position.

Allowed values:

  • directional (Directional)
  • non_directional (Non directional)

Popup Description. Add a title or a discription to help explain your tooltip

Animation

animation_speed number

Animation Duration.

Number format

localization.input_decimal_separator string

Decimal separator in data sheet. Used for interpreting your data. Only change if data is not displaying on the chart as expected.

Allowed values:

  • . (.)
  • , (,)

localization.output_separators string

Number format to display. How the numbers should appear on chart labels

Allowed values:

  • ,. (12,235.67)
  • ., (12.345,67)
  • . (12235.67)
  • , (12345,67)
  • . (12 235.67)
  • , (12 345,67)

label_format.prefix string

Prefix. Text to place in front of number

label_format.suffix string

Suffix. Text to place after number

label_format.n_dec number

Decimal places. Use negative integers to round to positive powers of ten (eg -2 rounds to the nearest 100)

Min: -10

Max: 10

label_format.advanced boolean

Advanced.

label_format.negative_sign string

Styling of negative numbers.

Allowed values:

  • -$nk (-$100k)
  • $-nk ($-100k)
  • ($nk) (($100k))
  • $(n)k ($(100)k)
  • none ($100k)

label_format.strip_zeros boolean

Remove trailing zeros.

label_format.strip_separator boolean

Hide thousands separator below 10,000. Turn off if you want four-digit numbers to include a separator, e.g. “1,234” rather than “1234”.

label_format.transform_labels boolean

Multiply/divide values.

label_format.transform string

Allowed values:

  • multiply (Multiply by)
  • divide (Divide by)
  • exponentiate (×10 to the power of)

label_format.multiply_divide_constant number

label_format.exponentiate_constant number

Scaling and sizing

chart_scale number

Chart scale.

Max: 1

allow_resize boolean

Allow embeds to resize. Checking this option allows the visualisation to resize so the chord diagram is always a square without white space to the sides or top/bottom.

Layout

layout.body_font font

Main font. This font will apply to the whole graphic by default, but you can optionally change the font for the title, subtitle, footer, etc in the Header and Footer settings panels.

layout.font_color color

Text color. This color will apply to the whole graphic by default, but you can optionally change the color for individual text elements, in other settings panels.

layout.background_color_enabled boolean

Color.

Allowed values:

  • true (On)
  • false (Off)

layout.background_image_enabled boolean

Image.

Allowed values:

  • true (On)
  • false (Off)

layout.background_color color

Background color.

layout.background_image_src url

Image URL.

layout.background_image_size string

Size.

Allowed values:

  • cover (Fill)
  • contain (Fit)
  • auto (Original)
  • 100% 100% (Stretch)

layout.background_image_position string

Position.

Allowed values:

  • top left (Top left)
  • top center (Top center)
  • top right (Top right)
  • center left (Center left)
  • center center (Center)
  • center right (Center right)
  • bottom left (Bottom left)
  • bottom center (Bottom center)
  • bottom right (Bottom right)

layout.max_width_target string

Maximum width. Apply a maximum width to just the main graphic or everything (main graphic plus header, footer, etc)

Allowed values:

  • none (None)
  • wrapper (Everything)
  • primary (Main graphic)

layout.max_width number

Maximum width. Leave blank to stretch to container width

Min: 50

layout.max_width_align string

Align.

Allowed values:

  • left (fa-align-left)
  • center (fa-align-center)
  • right (fa-align-right)

layout.layout_order string

Layout order.

Allowed values:

  • stack-default (data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABYAAAAdCAYAAAHZdKxuAAAAAXNSR0IArs4c6QAAANhJREFUSA3tVNEOwiAM7Iy/p2/wkTz6g5gjOVZZEepcjMmWLBTau95ugIh6lpzzLcb4wNpFJaRk9MIahxAyXmD7mC7BC2RlFbliQjFMpJTujOdGs/ECwRoP3rlKoEzNJlz3+CwutK0NLRVt2QhjggA9n2IGEKANMxmt0VVsEfxgzfX7zL3ZiqbXLjcKc8vEORk5/75mMB/7u11uuIpdbtDCc5R3l/s+e+pmHt1foza7Nv6IXOeHiqGk9zWtSk1cN2cPrItnYjZzHZEZYtacxHTiuANSO/xN8AS4uW8Rw1Gu2AAAAABJRU5ErkJggg==)
  • stack-2 (data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABYAAAAdCAYAAAHZdKxuAAAAAXNSR0IArs4c6QAAAMpJREFUSA3tVMsKwyAQNKW/l970Iz32Bw0jjKTrSLUY0oOBsO5rnOwYnTs9W0ppDyG8EcsOkw8uauu9T3jR2+75yJxBnnC4JxMxxlezg0V9VsJsIGz75TfKdlkpg3aPcT8TsPNRMJjZEIf5xaAAahUyE+RtfcZvtFLoFh95aFXxH4hCWpUoTCg7fxqUfB4yEcl/CJlNy5qbfuZA8m8CwJ77q2djSj50lnuAWbOAOQlXxCuRHxcUje2XzfgrYzBpHUXLkmxh181SpnEAB4Vg0DSGhHsAAAAASUVORK5CYII=)

layout.space_between_sections string

Space between sections.

Allowed values:

  • 0.5 (▁)
  • 1 (▃)
  • 1.5 (▄)
  • custom (...)

layout.space_between_sections_custom number

Custom.

Max: 100

layout.margin_top number

Top.

layout.margin_right number

Right.

layout.margin_bottom number

Bottom.

layout.margin_left number

Left.

layout.border.enabled boolean

Show borders around visualisation.

layout.border.top.width number

Top.

layout.border.top.style string

Style.

Allowed values:

  • solid (Solid)
  • dashed (Dashed)
  • dotted (Dotted)

layout.border.top.color color

Color.

layout.border.right.width number

Right.

layout.border.right.style string

Style.

Allowed values:

  • solid (Solid)
  • dashed (Dashed)
  • dotted (Dotted)

layout.border.right.color color

Color.

layout.border.bottom.width number

Bottom.

layout.border.bottom.style string

Style.

Allowed values:

  • solid (Solid)
  • dashed (Dashed)
  • dotted (Dotted)

layout.border.bottom.color color

Color.

layout.border.left.width number

Left.

layout.border.left.style string

Style.

Allowed values:

  • solid (Solid)
  • dashed (Dashed)
  • dotted (Dotted)

layout.border.left.color color

Color.

layout.header_align string

Alignment.

Allowed values:

  • left (fa-align-left)
  • center (fa-align-center)
  • right (fa-align-right)

layout.title string

layout.title_styling boolean

Change title styles.

layout.title_font font

Title Font.

layout.title_size string

Size.

Allowed values:

  • 1.4 (ᴀ)
  • 1.6 (A)
  • 2 (fa-font)
  • custom (...)

layout.title_size_custom number

Custom. Specify a custom responsive font size. Best results will be with values between 1.2 and 3

layout.title_weight string

Weight.

Allowed values:

  • bold (Bold)
  • normal (Regular)

layout.title_color color

Color.

layout.title_line_height number

Line height.

Max: 3

layout.title_space_above string

Space above.

Allowed values:

  • 0 (▁)
  • 0.5 (▃)
  • 1 (▄)
  • custom (...)

layout.title_space_above_custom number

Custom.

Max: 100

layout.subtitle string

layout.subtitle_styling boolean

Change subtitle styles.

layout.subtitle_font font

Subtitle Font.

layout.subtitle_size string

Size.

Allowed values:

  • 1.4 (ᴀ)
  • 1.6 (A)
  • 2 (fa-font)
  • custom (...)

layout.subtitle_size_custom number

Custom. Specify a custom responsive font size. Best results will be with values between 1.2 and 3

layout.subtitle_weight string

Weight.

Allowed values:

  • bold (Bold)
  • normal (Regular)

layout.subtitle_color color

Color.

layout.subtitle_line_height number

Line height.

Max: 3

layout.subtitle_space_above string

Space above.

Allowed values:

  • 0 (▁)
  • 0.5 (▃)
  • 1 (▄)
  • custom (...)

layout.subtitle_space_above_custom number

Custom.

Max: 100

layout.header_text string

layout.header_text_styling boolean

Styling.

layout.header_text_size string

Size.

Allowed values:

  • 1.2 (ᴀ)
  • 1.4 (A)
  • 1.6 (fa-font)
  • custom (...)

layout.header_text_size_custom number

Custom. Specify a custom responsive font size. Best results will be with values between 1.2 and 3

layout.header_text_weight string

Weight.

Allowed values:

  • bold (Bold)
  • normal (Regular)

layout.header_text_color color

Color.

layout.header_text_line_height number

Line height.

Max: 3

layout.header_text_space_above string

Space above.

Allowed values:

  • 0 (▁)
  • 0.5 (▃)
  • 1 (▄)
  • custom (...)

layout.header_text_space_above_custom number

Custom.

Max: 100

layout.header_border string

Allowed values:

  • top (Top)
  • bottom (Bottom)
  • none (None)

layout.header_border_width number

Width.

layout.header_border_color color

Color.

layout.header_border_style string

Style.

Allowed values:

  • solid (Solid)
  • dashed (Dashed)
  • dotted (Dotted)

layout.header_border_space number

Space. Space between border and header text

layout.header_logo_enabled boolean

Allowed values:

  • true (Enabled)
  • false (Disabled)

layout.header_logo_src url

URL.

layout.header_logo_height number

Height.

layout.header_logo_align string

Align. Align logo inside header or outer visualisation container

Allowed values:

  • outside (Outside)
  • inside (Inside)

layout.header_logo_position_inside string

Position.

Allowed values:

  • top (Top)
  • left (Left)
  • right (Right)

layout.header_logo_position_outside string

Position.

Allowed values:

  • left (Left)
  • right (Right)

layout.header_logo_margin_top number

Top.

layout.header_logo_margin_right number

Right.

layout.header_logo_margin_bottom number

Bottom.

layout.header_logo_margin_left number

Left.

layout.footer_align string

Alignment.

Allowed values:

  • left (fa-align-left)
  • center (fa-align-center)
  • right (fa-align-right)
  • justify (fa-align-justify)

layout.footer_text_size number

Size.

layout.footer_text_color color

Color.

layout.footer_styling boolean

Advanced footer styles.

layout.footer_font font

Font.

layout.source_name string

Source name.

layout.source_url string

Source url.

layout.multiple_sources boolean

Multiple sources.

layout.source_name_2 string

Source name.

layout.source_url_2 string

Source url.

layout.source_name_3 string

Source name.

layout.source_url_3 string

Source url.

layout.source_label string

Source label.

layout.footer_note string

Note.

layout.footer_note_secondary string

Note (secondary). The secondary note is placed below the source and primary note

layout.footer_logo_enabled boolean

Image.

Allowed values:

  • true (Enabled)
  • false (Disabled)

layout.footer_logo_src url

Image.

layout.footer_logo_src_light hidden

Image (light version). If provided this version will be used whenever the background colour is dark

Link.

layout.footer_logo_height number

Height.

layout.footer_logo_margin number

Margin.

layout.footer_logo_order string

Position.

Allowed values:

  • left (Left)
  • right (Right)

layout.footer_align_vertical string

V. align.

Allowed values:

  • flex-start (Top)
  • center (Center)
  • flex-end (Bottom)

layout.footer_border string

Allowed values:

  • top (Top)
  • bottom (Bottom)
  • none (None)

layout.footer_border_width number

Width.

layout.footer_border_color color

Color.

layout.footer_border_style string

Style.

Allowed values:

  • solid (Solid)
  • dashed (Dashed)
  • dotted (Dotted)

layout.footer_border_space number

Space. Space between border and footer text

Accessibility

layout.screenreader_hide_primary boolean

Screenreader mode for main visual container. Whether the main visual container is visible to screenreaders. (Text in the header and footer are always available to screenreaders.)

Allowed values:

  • true (Hidden)
  • false (Readable)

layout.screenreader_text_primary text

Screenreader description. A text alternative to the visual content that will only be visible to screenreaders, e.g. “The line chart shows China consistently higher than the other countries since 1990”. Do no replicate your title, since that will also be read by screenreaders.