Chord diagram
Updated a month ago to v9.1.0 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
API information
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: 9
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: "9",
bindings: {
connections: {
source: 0, // index of a column in your data
target: 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: "9",
bindings: {
connections: {
source: 0, // index of a column in your data
target: 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: "9",
bindings: {
connections: {
source: "ConnectionsHeader1",
target: "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: "9",
bindings: {
connections: {
source: "ConnectionsHeader1",
target: "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: "9",
data: {
connections: [
{
source: ...,
target: ...,
value: ...
},
...
]
},
...
}
And the full list of all possible properties is as follows:
{
template: "@flourish/chord-diagram",
version: "9",
data: {
connections: [
{
source: ...,
target: ...,
value: ...
},
...
]
},
...
}
Meanings of the template data keys:
- connections.source: source
- connections.target: target
- connections.value: A number specifying the size of the flow
Template settings
Options for opts.state.
Chords
opacity_default number
Default opacity. Opacity for the default view Max: 1
opacity_focused number
Focused opacity. Opacity for the selected and/or hovered chords Max: 1
opacity_defocused number
Defocused opacity. Opacity for the background chords when one is in focus Max: 1
selected_chords text
Highlight chords. You can highlight all of an arc's chords by typing the name of the arc. Alternatively, you can highlight individual chords by typing the name of the two arcs that it connects using the format:
Arc 1 >> Arc 2
If you wanted to highlight all chords from "Arc 3" and any chords between "Arc 1" and "Arc 2" you would write:
Arc 3
Arc 1 >> Arc 2
If you wish to highlight/unhighlight in the story editor you can do so by clicking on chords.
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 changes the label size based on the window size, subject to the specified min and max Allowed values:
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
Space below. As a percentage of the radius Max: 40
pad_angle number
Space between. In degrees Max: 180
label_alignment string
Alignment. Allowed values:
label_responsive boolean
Label text size. Auto changes the label size based on the window size, subject to the specified min and max Allowed values:
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
Label color.
use_label_color_arc boolean
Make the arc label color the same as the arc color.
Colors
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. Enter the label name for which you wish to set the color, followed by a colon and the desired color value.
Colors can be set using Hex, RGB, color names or RGBA, if you want to set the opacity. Multiple colors can be set using multiple lines. For example:
Party 1: red
Party 2: #4455AA
Party 3: rgb(30,168,26)
color.numeric_type string
Scale type. Allowed values:
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:
color.bin_mode string
Binning mode. Allowed values:
color.bin_count number
Number of bins.
color.bin_thresholds string
Custom thresholds. Enter your desired thresholds, separating them with a ";". For instance, "5;10;15".
Bins form as follows:
For "5;10;15", you'll get four bins based on your data's range.
color.sequential_palette string
Palette. Allowed values:
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:
color.sequential_custom_domain boolean
Domain. Allowed values:
color.sequential_domain_min number
Min.
color.sequential_domain_max number
Max.
color.diverging_palette string
Palette. Allowed values:
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:
color.diverging_custom_domain boolean
Domain. Allowed values:
color.diverging_domain_min number
Min.
color.diverging_domain_mid number
Mid.
color.diverging_domain_max number
Max.
gradient_type string
Chord color mode. Allowed values:
Popups
popup.show_popups boolean
Popups. Allowed values:
popup.is_custom boolean
Popup contents. Allowed values:
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:
popup.text_size number
Font size. Max: 10
popup.fill_color color
Fill colour.
popup.opacity number
Fill opacity. Max: 1
popup.padding number
Padding. Max: 10
popup.border_radius number
Radius. Corner radius of popup
popup.max_width number
Max width. Max: 50
popup_type string
Position. Allowed values:
popup_content text
Popup description. Add a title or a discription to help explain your tooltip
Animations
animation_speed number
Animation duration. The duration, in seconds, of transitions – for example between two slides in a story
Number formatting
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:
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. Enter a negative integer to round to a whole number with that many zeros. For example, -2 will round to the nearest hundred. Min: -10 Max: 10
label_format.advanced boolean
Advanced.
label_format.negative_sign string
Styling of negative numbers. Allowed values:
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 & sizing
chart_scale number
Chart scale. Max: 1
allow_resize boolean
Allow embeds to resize. Checking this option allows the visualization 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. 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, You can optionally change the color for individual text elements, in other settings panels.
layout.background_color_enabled boolean
Color. Allowed values:
layout.background_image_enabled boolean
Image. Allowed values:
layout.background_color color
Background color.
layout.background_image_src url
Image URL.
layout.background_image_size string
Size. Allowed values:
layout.background_image_position string
Position. Allowed values:
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:
layout.max_width number
Maximum width. Leave blank to stretch to container width Min: 50
layout.max_width_align string
Align. Allowed values:
layout.layout_order string
Layout order. Allowed values:
layout.space_between_sections string
Space between sections. Allowed values:
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:
layout.border.top.color color
Color.
layout.border.right.width number
Right.
layout.border.right.style string
Style. Allowed values:
layout.border.right.color color
Color.
layout.border.bottom.width number
Bottom.
layout.border.bottom.style string
Style. Allowed values:
layout.border.bottom.color color
Color.
layout.border.left.width number
Left.
layout.border.left.style string
Style. Allowed values:
layout.border.left.color color
Color.
layout.read_direction string
Read direction. This will change the reading direction of the main text elements on the page. It's not possible to adjust this on all elements, such as axes. Allowed values:
Note that when direction is set to right to left any alignment icons will be reversed.
layout.font_size_mobile_small number
layout.font_size_mobile_big number
layout.font_size_tablet number
layout.font_size_desktop number
layout.font_size_big_screen number
layout.breakpoint_mobile_small number
layout.breakpoint_mobile_big number
layout.breakpoint_tablet number
layout.breakpoint_desktop number
layout.breakpoint_big_screen number
Header
layout.header_align string
Alignment. Allowed values:
layout.title html
layout.title_styling boolean
Styling.
layout.title_font font
Title Font.
layout.title_size string
Size. Allowed values:
layout.title_size_custom number
Custom. Specify a custom responsive font size in rems. The best results will be with values between 1.2 and 3
layout.title_weight string
Weight. Allowed values:
layout.title_color color
Color.
layout.title_line_height number
Line height. Max: 3
layout.title_space_above string
Space above. Allowed values:
layout.title_space_above_custom number
Custom. Max: 100
layout.subtitle html
layout.subtitle_styling boolean
Styling.
layout.subtitle_font font
Subtitle Font.
layout.subtitle_size string
Size. Allowed values:
layout.subtitle_size_custom number
Custom. Specify a custom responsive font size in rems. The best results will be with values between 1.2 and 3
layout.subtitle_weight string
Weight. Allowed values:
layout.subtitle_color color
Color.
layout.subtitle_line_height number
Line height. Max: 3
layout.subtitle_space_above string
Space above. Allowed values:
layout.subtitle_space_above_custom number
Custom. Max: 100
layout.header_text html
layout.header_text_styling boolean
Styling.
layout.header_text_size string
Size. Allowed values:
layout.header_text_size_custom number
Custom. Specify a custom responsive font size in rems. The best results will be with values between 1.2 and 3
layout.header_text_weight string
Weight. Allowed values:
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:
layout.header_text_space_above_custom number
Custom. Max: 100
layout.header_border string
Allowed values:
- top (Top)
- bottom (Bottom)
- top_and_bottom (Top & bottom)
- none (None)
layout.header_border_width number
Width.
layout.header_border_color color
Color.
layout.header_border_style string
Style. Allowed values:
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
Image.
layout.header_logo_alt string
Alt text.
layout.header_logo_link_url string
Link.
layout.header_logo_height number
Height.
layout.header_logo_align string
Align. Align logo inside either the header or the main visualization container Allowed values:
layout.header_logo_position_inside string
Position. Allowed values:
layout.header_logo_position_outside string
Position. Allowed values:
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.
Footer
layout.footer_align string
Alignment. Allowed values:
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.footer_text_weight string
Weight. Allowed values:
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 html
Note. To add the time/date stamp of when the data was last updated add {{data_last_updated}}. For example, "Last updated at {{data_last_updated}}". To customize the format, use the advanced options below.
layout.footer_note_secondary html
Note (secondary). The secondary note is placed below the source and primary note. To add the time/date stamp of when the data was last updated add {{data_last_updated}}. For example, "Last updated at {{data_last_updated}}". To customize the format, use the advanced options below.
layout.advanced_note_styling boolean
Advanced.
layout.footer_timestamp_format string
Time/date stamp formatting. To change the date/time format of your timestamp, choose from the below options or provide a custom date format in d3-time-format syntax Predefined values:
layout.footer_logo_enabled boolean
Image. Allowed values:
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 color is dark
layout.footer_logo_alt string
Alt text.
layout.footer_logo_link_url string
Link.
layout.footer_logo_height number
Height.
layout.footer_logo_margin number
Margin.
layout.footer_logo_order string
Position. Allowed values:
layout.footer_align_vertical string
V. align. Allowed values:
layout.footer_border string
Allowed values:
- top (Top)
- bottom (Bottom)
- top_and_bottom (Top & bottom)
- none (None)
layout.footer_border_width number
Width.
layout.footer_border_color color
Color.
layout.footer_border_style string
Style. Allowed values:
layout.footer_border_space number
Space. Space between border and footer text
Accessibility
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 not replicate your title, since that will also be read by screenreaders.
layout.screenreader_label string
Screenreader label. A short text label given to the main Flourish embed wrapper to provide an accessible name that is only visible to screenreaders. Added in the form of an "aria-label".
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:
