Symbolizing Data Layers

Classify and style your layers for data exploration and mapping.

Layer symbology refers to the properties of how data is represented graphically. Using the symbology controls, you can adjust the point sizes, line weights, and colors of point, line, and polygon features. You can also classify numeric data according to standard methods — including equal interval, logarithmic, natural breaks, and quantiles — to identify and visually communicate patterns.

This article describes the controls of the Layer Style Tab, introduces the Symbology Editor, and outlines the basics of how to edit layer symbology. The following articles detail the controls for styling point, line, and polygon data; and classifying data. For details on extruding data, see Applying 3D Extrusion.

Layer Style Tab

Layer symbology details are shown in the Style tab of the Layer Details pane. To view layer symbology, select a layer (highlighting it as the active layer) in the Layers list. If not already selected, click on the Style tab.

The Style tab includes the following controls:

  • Edit symbology: Opens the symbology editor for the currently selected column.

  • Column: A list of all columns in the currently selected layer. Choose which column to display on the map.

  • Opacity: Controls the opacity of the currently selected layer.

  • Classes: Serves as a legend, displaying the data classes and symbology for the currently selected column.

Style tab controls

Increasing the opacity of the Public Transit Lines layer from the Style tab

Symbology Editor

The Symbology Editor contains the controls to adjust layer symbology. To open it, click Edit symbology in the Style tab. The options you see will vary depending on the feature type (point, line, or polygon) of the layer and the data type of the column you selected (categorical or numeric). The map will update dynamically as you make changes. Changes will be only be saved if you choose to save your settings.

Increasing stroke width of Public Transit Lines from the 'Edit Symbology' mode

How to Edit Layer Symbology

To edit layer symbology:

1. Click on the layer in the Layers list to activate it. The Layer Details pane will expand.

2. Select the column that you want to symbolize by selecting it from the Column list. If you want to symbolize all features using a single symbol, select the "No column (single symbol)" option.

3. Click Edit symbology. The symbology editor controls appear in the Layer Details pane. The options vary depending on feature type (point, line, or polygon) and the data type of the column you selected.

4. Define data classes for categorical or numeric data. See Classifying Data for details.

5. Select layer style options.

  • For point features, see Styling Point Data. You can adjust dot size, fill color, stroke width, stroke color, and opacity.

  • For line features, see Styling Line Data. You can adjust stroke width, stroke color, and opacity.

  • For polygon features, see Styling Polygon Data. You can adjust fill, stroke width, stroke color, and opacity, and extrude features in 3D.

6. Click Save to save your new symbology. Alternatively, you can click Discard to discard your changes, or click Restore Defaults to restore the default settings for the column (if any).

Symbology settings for individual columns within a single layer are saved so that you can switch between mapped columns without losing your data classifications and style settings. All layer symbology is linked to individual users so you can maintain unique settings.

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