Dot Plots

Learn about building and configuring dot plots in Mappica.

Overview

Dot Plots display data points as individual dots positioned along axes, making them ideal for showing distributions, comparisons, and patterns in datasets. They are particularly effective for displaying categorical data with numeric values, allowing for easy comparison between categories while maintaining clarity even with overlapping data points.

Dot plots can display single or multiple series of data, with different colors and symbols to distinguish between series. They are especially useful when you want to show individual data points rather than aggregated values, making patterns and outliers clearly visible.

Setup

In the Setup section, under the Chart tab, you can assign the following properties:

  • The name will be used to reference it in the Layers tab and on the canvas.
  • The top, right, bottom, and left Margin that will be added between the chart axes and the edge of the chart container.
Tip

Because the margin sets the space between the chart axes and the edge of the container, ensure you add enough margin for any axis ticks or labels. If needed, use options in the Axes section such as Rotate Ticks to constrain the size of tick and label text.

  • The Size Ratio of the chart container. Since the chart will always take up the available width inside its parent section, the size ratio effectively determines the chart's height.
  • Optionally, the chart's Minimum Height and/or Maximum Height. If the height calculated by the size ratio is smaller than the Minimum Height or larger than the Maximum Height, then the Minimum Height or Maximum Height is used instead of the size ratio.

Connecting to Datasets

In the Dataset section, you can select the dataset for your chart. If you need to add a dataset, this can be done by selecting New Dataset in the Project tab.

Pro

If you are on the Pro plan, you can upload your own files (in csv format) to use as datasets, by clicking New Dataset and then Upload Dataset.

After you have selected a dataset, you can optionally enable the Prefilter Dataset switch, which lets you filter the data that is supplied to the chart. The filter is a "prefilter" because it is applied before the visualization is generated; end users are unable to adjust the filter dynamically.

Next, the Data Format is displayed. You can select either Wide Data or Long Data. The data format should reflect the structure of the selected dataset. It also determines the fields that will need to be set for the chart.

Finally, choose the Fields that should be used to construct the chart:

  • Horizontal Axis Field (for long data): The chart's independent variable, typically a categorical or date field.
  • Vertical Axis Field (for long data): A numeric, percent, currency, or measurement field that serves as the chart's dependent variable.
  • Series Fields (for wide data): The chart's dependent variables, which are number, percent, currency, or measurement fields used for each dot series.

Connecting to Filters

You can establish connections to filter elements under the Chart tab, in the Connections section, by making a selection under Filter.

A Filter element can be styled as a series of checkboxes, a dropdown menu, or a slider. Values from the specified Filter Field appear as individual checkboxes, dropdown menu items, or (for numeric filtering) slider values. A given chart can be connected to one or more filters, and the same filter can be connected to multiple charts or other elements.

When a filter element is connected to a chart, it dynamically controls the dataset records displayed in the chart based on the user's selections. Filters can also adjust the chart's axis range dynamically, provided one of the chart's axis fields is the same as the filter's Filter Field and the Minimum and Maximum Range values of that axis are set to auto.

Additionally, filter elements can inherit color formatting from a chart, provided that the chart is using Long Data format and the chart's Color Field is the same as the filter's Filter Field. For more information, see the Color Formatting section of the documentation for filter elements.

Tip

If your chart uses Wide Data format, use a Selector element instead of a filter to dynamically control the chart color series.

Typically, the Filter element you connect to will use the same Dataset as the chart element. However, this is not strictly necessary. If the filter and chart elements use different datasets, the filter will only affect the chart if the chart's dataset contains a field (column) with the same name as the Filter Field in the filter element. In this case, the values in these fields must at least partially align for the filter to take effect. Any non-matching values between the fields will be ignored during filtering.

Connecting to Selectors

If you are using Wide Data format, you can establish a connection to a selector element under the Chart tab, in the Connections section, by making a selection under Selector.

Selector elements control which series fields are displayed in connected elements that use a wide data format. Selectors can be displayed as checkboxes, dropdowns, or legends. While a chart can be connected to only one selector, a single selector can be connected to multiple charts and other elements that use series fields. Once connected, the selector element dynamically controls the dataset fields (columns) passed to the chart as series fields based on user selections.

Sorting

You can choose how to sort the chart data under the Chart tab in the Sort section. Choose either to sort by the independent or dependent variable. In both cases, you can also choose to reverse the natural sort order.

Axes

The Axes section of the Chart tab can be used to configure the Horizontal Axis and Vertical Axis respectively.

  • Add Label: When enabled, label text appears adjacent to the axis. You can also align the label text.
  • Customize Range: Specify a custom minimum and maximum value for the chart axis.
  • Set Axis Line Location: When enabled, this option lets you control the position of the axis line. Auto places the axis line at the bottom of the chart (in the case of the horizontal axis) or the left of the chart (in the case of the vertical axis). Zero aligns the axis to the zero value and Hidden removes the axis line entirely. If this option is turned off, the chart's independent axis line will be displayed in a default location and the dependent axis line will be hidden (Pro users can adjust these default settings in the Theme page).
  • Customize Ticks: When enabled, you can control which tick values will be displayed on the axis. Values lets you specify exact tick values, which should be separated with commas. Choose Count to set an approximate number of ticks (this option is only available on axes displaying continuous data). Or choose Hidden to remove ticks from the axis.
Tip

If you choose to specify exact tick values, ensure that they don't overlap with one another on tablet and mobile viewports.

  • Rotate Ticks: On horizontal axes, you can rotate tick labels to angles of , 30°, 45°, 60°, or 90°. This can improve readability, especially when dealing with long or overlapping tick labels.
  • Use Short Format: On the dependent axis, you can display axis tick values in a compact format, such as 1K for 1,000 or 1M for 1,000,000.

The following chart formatting option applies to both axes:

  • Clip Chart: Restrict the chart's dots and any annotations from extending beyond the boundaries of the chart container, ensuring all items remain within the outermost values on both axes.

Colors

Color formatting is defined in the Colors section under the Chart tab.

If the chart uses Wide Data format, separate colors can be assigned to each of the selected dot series.

If the chart uses Long Data format, you can specify a Color Field, which can be a text field or numeric (number, currency, percent, or measurement) field from the selected dataset. If you select a text field, each unique value in that field will be treated as a series and can be assigned a color. For numeric fields, you can configure a Color Gradient, Domain Minimum and Maximum, and Color Scale. These features are explored in greater detail in our Colors page.

Settings

In the Settings section under the Chart tab, specify the following options:

Symbol: Choose the symbol type for displaying data points. Options include:

  • "Circle" (the default) displays filled circles
  • "Circle (Outlined)" displays outlined circles
  • "Square" displays filled squares
  • "Square (Outlined)" displays outlined squares
  • "Diamond" displays filled diamonds
  • "Triangle" displays filled triangles
  • "Cross" displays cross symbols
  • "Plus" displays plus symbols
  • "Star" displays star symbols

Symbol Size: Adjust the size of the symbols in pixels. The default size is 4px.

Symbol Opacity: Control the transparency of the symbols, with 100% being completely opaque and 0% being completely transparent.

Annotations

In the Annotations section under the Chart tab, you can create annotations by clicking the Add Annotation button. The position of each annotation is specified with the "X Location" and "Y Location" fields. If the chart's horizontal axis uses a date field, you can specify the X location in YYYY/MM/DD or YYYY format.

The following items can be added to each annotation:

  • Add Text: Add text to the annotation using the Text field. Choose a Color for the text, and specify its position relative to the X and Y locations using the Text Position setting. Available positions include "Top," "Right," "Bottom," "Left," or the default "Center," which centers the text vertically and horizontally over the X and Y location.
  • Add Line: Add a line annotation to your chart. Use the Direction setting to render either a "Horizontal" line, a "Vertical" line, or line in both directions ("Both"). Choose a Color for the line.
  • Add Symbol: Add a symbol annotation to your chart. Select the symbol type from the Symbol dropdown, which includes options such as "Asterisk," "Circle," "Cross," "Diamond," "Hexagon," "Plus," "Square," "Star," "Times," and "Triangle." Customize the symbol's Color and specify its Width in pixels.

Tooltips

Tooltips can be enabled by selecting the Chart tab, navigating to the Tooltip section, and selecting Display Tooltip. These are automatically configured to display the fields selected in the chart.