Setting and Managing Layers > Layer Properties > Setting Symbology

Graduated Symbol

When you need to quantify the attributes of the map, you can use the graduated color or graduated symbol to classify your map. The latter represents the different quantities by varying the symbol size; that's what we call the graduated symbol map. Graduated symbol uses a series of symbols to present the numbers in different ranges. Generally, the attribute values are classified to ranges or intervals, like 0-5, 6-10, or from the lowest to the highest. For instance, the map bellow shows the area size of parks in Taipei with the dots of different sizes. Each interval is 10,000 m^2 and presented with a symbol of the specific size.

To set graduated symbols, choose "Graduated Symbol" in "Show" drop-down list in Layer Properties window. Then, choose a field for "Value field." In "Normalization", you can choose whether you need to divide the value field by any field. If no, you do not have to choose the normalization field (the default is none). Then, click the "Classes" drop-down list and choose the classes you need (you can directly enter the value).

The color, style of the graduated symbols can be modified respectively. If you want to modify all of the symbols, you can click

to modify them. However, in Symbol Selector window, users are not allowed to modify symbol size. To modify symbol size, users can input the value of symbol size (the default is from 5 to 20) at the bottom of the Symbology tab, and the system will set the symbol size according to the settings. In addition, users are also able to modify size of each symbol by double-clicking the target symbol shown in Symbology tab.

As all the settings are finished, click "OK" to finish graduated symbol setting. As to the manipulation of other symbols, please refer to Unique Values and Graduated Color.