Parliament chart

A visualisation that positions dots in a hemicycle shape. Useful for visualising parliament layouts.

Updated 5 years ago to v2.1.2 by Flourish team

How to use this template

This template is ideal for showing the number of parliament seats owned by each party. It provides you with the ability to examine the difference in seats held between two elections, with an option to have a nice animation when displaying the change. The chart is accompanied by a table and a legend, both of which are optional. The table provides a summary of the seat change between the two elections. The legend on default is turned off, but can be added, and has a mouseover effect when hovering over one of the party names. The chart will also flip vertically on mobile.

Data requirements

You must have at least two columns. One with the party name, and another with the total number of seats for the current election. There is also an optional column which can represent the previous election.

Tips

  • You can adjust the number of seats in the parliament chart to your liking. By default, the number of seats is at 650, but you can change it to 435 seats, for example, if you're making a chart about US parliament seating.

  • Tweak the colours with the Automatic colour scheme, or change the colour for one party, or all the parties with the Custom party colours.

  • You can add/remove the table, the legend, the buttons, the animation.

Credits

Created by the Flourish team. 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/parliament-chart

version: 2

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: {
        data: [
            [ "DataColumn1Value1", "DataColumn2Value1",
            [ "DataColumn1Value2", "DataColumn2Value2",
            [ "DataColumn1Value3", "DataColumn2Value3",
            ...
        ]
    }
}

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/parliament-chart",
    version: "2",
    bindings: {
        data: {
            party: 0, // index of a column in your data
            seats_current: 1, // index of a column in your data
        }
    },
    data: {
        data: [
            [ "DataColumn1Value1", "DataColumn2Value1",
            [ "DataColumn1Value2", "DataColumn2Value2",
            [ "DataColumn1Value3", "DataColumn2Value3",
            ...
        ]
    }
}

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

{
    template: "@flourish/parliament-chart",
    version: "2",
    bindings: {
        data: {
            party: 0, // index of a column in your data
            seats_current: 1, // index of a column in your data
            seats_previous: 2, // index of a column in your data
        }
    },
    data: {
        data: [
            [ "DataColumn1Value1", "DataColumn2Value1",
            [ "DataColumn1Value2", "DataColumn2Value2",
            [ "DataColumn1Value3", "DataColumn2Value3",
            ...
        ]
    }
}

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:

{
        data: [
            { "DataHeader1": ..., "DataHeader2": ..., ... },
            { "DataHeader1": ..., "DataHeader2": ..., ... },
            { "DataHeader1": ..., "DataHeader2": ..., ... },
            ...
        ]
    }

... 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/parliament-chart",
    version: "2",
    bindings: {
        data: {
            party: "DataHeader1",
            seats_current: "DataHeader2",
        }
    },
    data: {
        data: [
            { "DataHeader1": ..., "DataHeader2": ..., ... },
            { "DataHeader1": ..., "DataHeader2": ..., ... },
            { "DataHeader1": ..., "DataHeader2": ..., ... },
            ...
        ]
    }
}

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

{
    template: "@flourish/parliament-chart",
    version: "2",
    bindings: {
        data: {
            party: "DataHeader1",
            seats_current: "DataHeader2",
            seats_previous: "DataHeader3",
        }
    },
    data: {
        data: [
            { "DataHeader1": ..., "DataHeader2": ..., ... },
            { "DataHeader1": ..., "DataHeader2": ..., ... },
            { "DataHeader1": ..., "DataHeader2": ..., ... },
            ...
        ]
    }
}

(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/parliament-chart",
    version: "2",
    data: {
    data: [
        {
            party: ...,
            seats_current: ...
        },
        ...
    ]
},
    ...
}

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

{
    template: "@flourish/parliament-chart",
    version: "2",
    data: {
    data: [
        {
            party: ...,
            seats_current: ...,
            seats_previous: ...
        },
        ...
    ]
},
    ...
}

Meanings of the template data keys:

  • data.party: party
  • data.seats_current: This should point to the column with the most recent election data
  • data.seats_previous: This data is used to compare the most recent election results to a previous one

Template settings

Options for opts.state.

Parliament layout

num_of_seats number

Number of seats.

Min: 1

Max: 40000

hemicycle_arc number

Size of arc.

Min: 10

Max: 360

circle_inner number

Inner space.

Max: 90

manual_row_count boolean

Number of rows.

Allowed values:

  • false (Auto)
  • true (Fixed)

num_of_rows number

Rows.

Min: 1

Colours

color.palette colors

Palette.

color.extend boolean

Auto-extend. Automatically generate additional colours when needed to avoid the palette colours being used more than once. Added colours are based on the average lightness and chroma values of the palette. This works best if the palette’s colours do not have very high or low saturation.

color.advanced boolean

Fine tune. Fine tune how additional colours are added to the palette.

color.hue_rotation_angle number

Hue rotation for added colours. Angle, in degrees in HCL colourspace, between one generated colour and the next. The default value, ~360/(Golden ratio), ensures adjacent hues are not too similar.

Max: 360

color.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)

opacity number

Opacity.

Max: 1

unassigned_color color

Unassigned.

bg_color color

Background.

Buttons

use_buttons boolean

Allow user to switch to earlier election result.

margin_button number

Margin.

Legend

show_legend boolean

Show legend.

use_hover_animation boolean

Filter dots when hovering over legend. If unchecked then there will no longer be a hover animation

legend_align string

Align legend.

Allowed values:

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

Table

show_table boolean

Show table.

gain_color color

Gain color.

loss_color color

Loss color.

default_text_color color

Default color.

header_weight string

Header text.

Allowed values:

  • bold (Bold)
  • normal (Normal)
  • italic (Italic)

seat_change_label string

Seat change label.

margin_table number

Margin.

seat_format.prefix string

Prefix. Text to place in front of number

seat_format.suffix string

Suffix. Text to place after number

seat_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

seat_format.strip_zeros boolean

Remove trailing zeros.

seat_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”.

seat_format.transform_labels boolean

Multiply/divide values.

seat_format.transform string

Allowed values:

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

seat_format.multiply_divide_constant number

seat_format.exponentiate_constant number

header.title string

Title.

header.subtitle string

Subtitle.

header.color color

Color.

header.align string

Alignment.

Allowed values:

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

header.margin number

Margin.

header.margin_advanced boolean

Advanced margin settings.

header.margin_top number

Top.

header.margin_right number

Right.

header.margin_bottom number

Bottom.

header.margin_left number

Left.

footer.source_name string

Source name.

footer.source_url string

Source url.

footer.multiple_sources boolean

Multiple sources.

footer.source_name_2 string

Source name.

footer.source_url_2 string

Source url.

footer.source_name_3 string

Source name.

footer.source_url_3 string

Source url.

footer.source_label string

Source label.

footer.note string

Note.

footer.size number

Size.

footer.color color

Color.

footer.align string

Alignment.

Allowed values:

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

footer.margin number

Overall.

footer.margin_top number

Top.

footer.margin_right number

Right.

footer.margin_bottom number

Bottom.

footer.margin_left number

Left.

footer.margin_advanced boolean

Advanced.

Animations

animation_duration number

Animation duration. How long the seats take to "flip" when changing party, in seconds

animation_stagger number

Animation spread. How many seconds to spread the seat animations across

animate_on_load boolean

Animate on load. Whether to animate the seats when the visualisations first loads

Max width

max_width number

Max width. The parliament chart can get quite big, you can limit it by setting a max width. If you don't want a max width, just set this setting to a very high number

Min: 100

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:

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