Modify Graduated Symbol Thematic Map

Instructions for use

In the "Graduated Symbol Thematic Map" window, you can modify various parameters of the graduated symbol thematic map to achieve a thematic map effect that better meets your needs.

Operational Steps

  1. In the layer manager, select a graduated symbol thematic map layer, right-click the "Modify Thematic Map" command, or double-click the thematic layer. The "Graduated Symbol Thematic Map" window will pop up, displaying the settings information of the currently selected graduated symbol thematic map.
  2. Thematic Map Layer: Shows the name of the current thematic map.
  3. Expression: Displays and sets the thematic variable used to create the current graduated symbol thematic map, which can be a single property field or a mathematical expression of fields.
    • Click the drop-down button on the combo box to the right of "Expression:". The drop-down list displays all property fields of the vector dataset used for the current graduated symbol thematic map.
    • In the drop-down list, select the thematic variable (a single property field) for the current graduated symbol thematic map layer. You can also click "Expression..." in the drop-down list to open the "SQL Expression" dialog and build a field expression as the thematic variable for the graduated symbol thematic map.
    Notes:
    • When creating a thematic map for data with Oracle Plus or SQL Plus engine types, the field expression must be a field value or field operation, such as (SmID) or (SmID + 1). Conditional expressions are currently not supported for setting thematic map fields. If the field expression is a conditional expression, e.g., "SmID > 100", the thematic map creation will fail, and the output window will display "Thematic map update failed".
  4. Classification Method: Determines the size of graduated symbols. Click the drop-down button to see all resampling methods for level values provided by the application. Select an appropriate resampling method from the list based on mapping needs.
    • Constant: Performs classification calculations based on the linear proportion of original values in the attribute table.
    • Square Root: Performs classification calculations based on the proportion of the square root of original values in the attribute table.
    • Logarithm: Performs classification calculations based on the proportion of the natural logarithm of original values in the attribute table.
  5. Base Value: Sets the numerical value represented by the system marker size. Based on this value, the system automatically calculates the marker size for other values according to the classification method. A larger base value results in a smaller final display size for point symbols. The valid range of the base value is the same as that of the thematic variable.
    • Enter the base value in the text box on the right.
  6. Symbol Style Settings: Click the button to the right of the "Positive", "Show Zero", and "Show Negative" labels to open the "Styles" window and set the style for positive base value, zero value, and negative graduated symbols. Before setting styles for zero or negative values, you must first select the checkbox to the left of the corresponding category. Changes to the marker style for positive base value, zero, and negative values do not affect each other.
    • Positive Base Value Style: Sets the rendering style for graduated symbols when the expression value is positive. Click the button to the right of this label to open the "Styles" window (i.e., the "Symbol Library" window; for specific operations, refer to: "Symbol Library" Window), where you can set the display style for positive base value graduated symbols.
    • Show Zero: If this checkbox is selected, objects with an expression value of zero can be rendered with the thematic style; otherwise, they are not rendered. Click the button to the right of this label to open the "Styles" window (i.e., the "Symbol Library" window; for specific operations, refer to: "Symbol Library" Window), where you can set the display style for zero value graduated symbols.
    • Show Negative: If this checkbox is selected, objects with a negative expression value can be rendered with the thematic style; otherwise, they are not rendered. Click the button to the right of this label to open the "Styles" window (i.e., the "Symbol Library" window; for specific operations, refer to: "Symbol Library" Window), where you can set the display style for negative value graduated symbols.
    • Flow: If this checkbox is selected, the rendering style of the thematic map can flow display, meaning graduated symbols will move as the map changes to optimize the display of all elements. When the flow effect is enabled, do not use partial refresh functionality, as it may cause incorrect display (partial refresh is not supported in SuperMap iDesktopX).
  7. Offset Settings:
    • Offset Unit: The drop-down button to the right of this label sets the unit for offset values. Click the drop-down button; in the menu, the system provides two offset units: "Unit" and "0.1mm" for selection. "0.1mm" means the symbol offset is in units of 0.1mm; "Unit" means the offset aligns with the map coordinate system's unit.
    • Offset X: Sets the X offset of graduated symbols relative to the objects they represent. You can directly enter a numerical value or select a numerical field from the layer to use its value as the offset.
    • Offset Y: Sets the Y offset of graduated symbols relative to the objects they represent. You can directly enter a numerical value or select a numerical field from the layer to use its value as the offset.
    • Show Leader Line: If this checkbox is selected, a leader line connects graduated symbols to the objects they label when offset. The "Line Style" button to the right becomes enabled. Click it to open the "Styles" window, where you can set the symbol style for the leader line; refer to: Line Symbol Style Settings.
  8. All parameters in the "Graduated Symbol Thematic Map" window are reflected in real-time on the corresponding thematic map layer in the current map, achieving a WYSIWYG effect. You can also disable real-time refresh by unchecking the "Enable Instant Refresh" checkbox at the bottom of the dialog. If "Enable Instant Refresh" is unchecked, click the "Apply" button at the bottom after setting parameters to apply them to the current thematic map.
Notes:
  • Both created and modified graduated symbol thematic maps can be saved as templates for application to other layers' thematic map creation. For details on saving as a thematic map template, refer to: Save to Thematic Map Template Library.
  • When creating a thematic map using the template method, you can directly select a saved template from the "Template" drop-down menu to apply it to other thematic maps.

Related Topics

Create a Graduated Symbol Thematic Map