– To create a Bubble map of various points and their PH values using graduated symbol sizes.
-Labeling the Point features with their PH value.
FOR SAMPLE DATA CLICK THIS LINK BELOW:
(kindly attribute the production of this data to www.mapsnigeriainitiative.wordpress.com)
Let us have a look at our dataset. In the Table of Contents, we have a Point feature layer which has on its attribute table a field containing the PH values of the different points. The goal here is to use graduated symbol sizes to create a Bubble map with the values in the attribute field –‘PH’.
Right Click on the Point feature layer > Properties.
In the Layer Properties window, Click on the tab- Symbology (red boxed).
Then since we are dealing with quantitative data, under the features, click on Quantities (red box 2).
1) Select Graduated symbols under quantities (2) In the Value option, select the attribute field of interest- PH (3) Define the number of classes the data will be classified into. (4) Define the range of the symbol size.
A Bubble map is created in the screenshot below. Notice that the symbol sizes are graduated according to increasing value of PH.
The goal will be to label the point features with the PH values displayed right inside the marker.
Right Click the Point feature layer and go to Properties.
Click on the Labels tab. Check the box titled ‘Label features in this layer’. Select the attribute field whose values will be used to label the features. Choose font and font size. Next Click on Placement Properties –see cursor arrow position.
In this window-Placement Properties- Select the option in the red box. Click Ok
Next in the Label window, Click on the Label Styles tab. The Label Style Selector window will open. Select a style and Click Ok.
The labels are placed inside the symbols here in the screenshot below.