Styling Polygon Layers

  1. Click the Options icon to the right of your polygon layer name in the Legend.

    Note: The Legend shows the current layer style below the layer name (the red square in the example to the right). New layers are unclassified as the default style.

  2. Click Edit Style in the menu. The Style Editor opens.

    There are four options for a polygon layer: Fill Color, Opacity, Line Color, and Line Width. The sections below explain how to style these visual attributes for polygon layers in two primary ways: unclassified and classified. (See Classifying Data Overview above for more information.)

Styling Unclassified Polygon Layers

To change the visual attributes of unclassified data, use the drop-down menus on the left side of the Style Editor.

Fill Color: Click the down arrow to open the fill color menu. Select the fill color by clicking on a color swatch. Your selected fill color appears in the Style Editor, and becomes the fill color of your polygon layer.

Opacity: Select the opacity of the fill color from the drop-down menu. The range of opacity is 0% (no fill color visible) to 100% (solid fill color). A fill color with 0% opacity is not visible on the map. Your selected opacity percent appears in the Style Editor, and is applied to the fill color of your polygon layer.

Line Color: Click the down arrow to open the line color menu. Select the line color by clicking on a color swatch. Your selected line color appears in the Style Editor, and the lines of your polygon layer.

Line Width: Select the line width from the drop-down menu. Your selected line width appears in the Style Editor, and is applied to the lines of your polygon layer.

Styling Classified Polygon Layers

Classifying on Fill Color

  1. Click the ramp button for Fill Color. The Ramp Editor opens.

  2. Select the field you want to tie the style variation to from the Select Field drop-down menu.

  3. Click the radio button above a color ramp to select it.

    Note: Depending on the type of data contained in the selected field, the Ramp Editor displays stepped ramps, or a combination of stepped and smooth ramps.

Stepped and Smooth Ramps Overview

The type of ramp that you choose is an important part of the visual classification scheme of your data, and the effectiveness of your analysis. It determines the classification methods that you can select.

Stepped ramps are composed of individual color swatches. Each color swatch has a different value. The colors in smooth ramps are blended together.

Stepped ramps and smooth ramps have different classification methods:

  • Stepped Ramps: In the Ramp Editor, you must select a Classification Method and # of Classes for stepped ramps. There are four types of classification methods. Each method classifies data in a different way. Selecting the best method for your data set optimizes your data classification. The # of Classes you select determines the range of values represented by the individual color swatches of a stepped ramp. It is the best practice to select 5 to 7 classes for a stepped ramp. (See Tips on Classifying Data below for more information.)

    In the Ramp Editor, the Review and Modify Classes table populates based on your selected Classification Method and # of Classes. You can make modifications in the table if desired, such as changing individual colors of your selected ramp.

  • Smooth Ramps: Select a smooth ramp if you’d like to visually differentiate a wide range of values on the map. In the Ramp Editor, the Classification Method and # of Classes are grayed out. They do not apply to smooth ramps. The Review and Modify Classes table automatically populates with three color swatches, and the minimum, median, and maximum field values for your selected smooth ramp. You can make modifications in the table if desired, such as changing a color.

Stepped Ramps

For a Stepped Ramp selection, you must select a Classification Method and # of Classes.

Classification Method and # of Classes

  • Classification Method: Select Natural Breaks, Distinct, Quantile, or Equal Interval from the drop-down menu (See Tips on Classifying Data below for definitions and tips).

  • # of Classes: Select the number of classes from the drop-down menu.

    Tip: The # of Classes sets the number of value ranges that have a distinct color. It is the best practice to select 5 to 7 classes. If you select too many classes, it is generally difficult to gain insight from the color scheme on the map. If you would like to visually differentiate many classes, use a smooth color ramp. (See Tips on Classifying Data below for more tips).

Review and Modify Classes Table

The Review and Modify Classes table enables you to try out different classification schemes before applying one:

  • Based on your choice of Classification Method and # of classes, the Review and Modify Classes table populates with the fill color, value, and label for your selected data field.

  • To further modify your classification scheme, you can make these selections in the table:

    • Color: Click on any ramp color to change it. The Color Selector opens (See Tips for Using the Color Selector below).

    • Value: Click a value to enter a new left end-point in the Edit Value window.

    • Label (Optional): Type a label for any data value. The Legend displays your label instead of the value.

To apply your classification scheme, click the OK button at the bottom of the Ramp Editor. The Fill Color button in the Style Editor displays your selected ramp.

Smooth Ramps

The Classification Method and # of Classes do not apply to smooth ramps. They are grayed out.

You can modify the attributes in the Review and Modify Classes table if desired:

  • Color: Click on any ramp color to change it. The Color Selector opens (See Tips for Using the Color Selector below).

  • Value: Click a value to edit it in the Edit Value window.

  • Label (Optional): Type a label for any data value. The Legend displays your label instead of the value.

To apply your classification scheme, click the OK button at the bottom of the Ramp Editor. The Fill Color button in the Style Editor displays your selected ramp.

Classifying on Opacity

Note: The Opacity and Fill Color options work together. A fill color with 0% opacity is not visible on the map. The range of opacity is 0% (no fill color visible) to 100% (solid fill color).

  1. Click the ramp button for Opacity. The Ramp Editor opens.

  2. Select a field you want to tie the style variation to from the Select Field drop-down menu.

  3. Click the radio button above an opacity ramp to select it.

    Note: Depending on the type of data contained in the selected field, the Ramp Editor might display two types of ramps: stepped and smooth.

  4. Select a Classification Method and # of Classes. Based on your choices, the Review and Modify Classes table populates with the opacity, value, and label for your classified data field. (See Tips on Classifying Data below for definitions and tips.)

    Note: Classification Method and # of Classes do not apply to smooth ramps. They are grayed out.

  5. In the Review and Modify Classes table, you can change the opacity assigned to your classes, click a value to edit the left end-point, or type a label for any data value. (The Legend displays your label instead of the value.)

    To apply your classification scheme, click the OK button at the bottom of the Ramp Editor. The Opacity button in the Style Editor displays your selected ramp.

Classifying on Line Color

Note: Line color is the same as border color. It is not recommended that you classify on line color for adjacent polygon layers because the line colors of adjacent polygons overwrite one-another. This causes the loss of some of your classifications.

  1. Click the ramp button for Line Color. The Ramp Editor opens.

  2. Select a field you want to tie the style variation to from the Select Field drop-down menu.

  3. Click the radio button above a line color ramp to select it.

    Note: Depending on the type of data contained in the selected field, the Ramp Editor might display two types of ramps: stepped and smooth.

  4. Select a Classification Method and # of Classes. Based on your choices, the Review and Modify Classes table populates with the bordercolor, value, and label for your classified data field. (See Tips on Classifying Data below for definitions and tips.)

    Note: Classification Method and # of Classes do not apply to smooth ramps. They are grayed out.

  5. In the Review and Modify Classes table, you can click on any Bordercolor to change it, click a value to edit the left end-point, or type a label for any data value. (The Legend displays your label instead of the value.)

    Tip: When you click on a Bordercolor, the Color Selector opens. See Tips for Using the Color Selector below for more information.

    To apply your classification scheme, click the OK button at the bottom of the Ramp Editor. Each polygon on the map is assigned a border color from your selected ramp. The Line Color button in the Style Editor displays the ramp.

Classifying on Line Width

Note: It is not recommended that you classify on line width for adjacent polygon layers because the line widths of adjacent polygons overwrite one-another. This causes the loss of some of your classifications.

  1. Click the ramp button for Line Width. The Ramp Editor opens.

  2. Select a field you want to tie the style variation to from the Select Field drop-down menu.

  3. Click the radio button above a line width ramp to select it.

    Note: Depending on the type of data contained in the selected field, the Ramp Editor might display two types of ramps: stepped and smooth.

  4. Select a Classification Method and # of Classes. Based on your choices, the Review and Modify Classes table populates with the size, value, and label for your classified data field. (See Tips on Classifying Data below for definitions and tips.)

    Note: Classification Method and # of Classes do not apply to smooth ramps. They are grayed out.

  5. In the Review and Modify Classes table, you can change the size of the line width assigned to your classes, click a value to edit it, or type a label for any data value. (The Legend displays your label instead of the value.)

    Tip: It is best practice to limit line width to a size range of no more than 1 - 12.

To apply your classification scheme, click the OK button at the bottom of the Ramp Editor. The Line Width button in the Style Editor displays your selected ramp.