new SuperMap.ThemeDotDensity(options)
The ThemeDotDensity uses some dots with the same size and shape to represent the distribution range, quantitative properties and distribution density. The number of dots and the meanings represented by the dots are decided by the content.
The ThemeDotDensity takes advantage of one numerical attribute information (the thematic value) of the layer to map as different grades. Each grade is represented by different number or density of dots.
This thematic value disposition in each partition is reflected in the relative quantity variance in different region. It is generally used in the maps that have quantitative properties.
such as the classification of the food production in different regions, GDP, population, etc, which is mainly for the region or area features, so the ThemeDotDensity is applicable to the region dataset.
Note: The dot distribution in the ThemeDotDensity which is random doesn’t represent the actual distribution locations.
Even when the related settings are the same totally, the thematic map made every time has the same number of points, but the locations of the points are different.
| Name | Type | Description | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
options |
Object |
The parameters.
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Extends
Members
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dotExpressionstring
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Creates the fields or field expressions for the ThemeDotDensity. The source of the dot numbers or the intensity.
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memoryDataSuperMap.ThemeMemoryData
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The ThemeMemoryData
The way of making thematic maps with the ThemeMemoryData and the ways of making thematic maps are mutually exclusive, the former has higher priority。 The first parameter represents the thematic value, that is, the data set is used to do the values of the fields or expressions of the thematic graph. The second parameters represent the external values. In the production of a thematic map, the external value is used instead of the topic value to make the corresponding thematic maps. -
styleSuperMap.ServerStyle
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The style of the ThemeDotDensity.
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typestring
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type of the thematic mapping.
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valuenumber
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The quantity of each dot represented in the Dot Density thematic map.
The value that each dot represents is related with map scale and dot size. Generally,
the dot value is decided by calculating the value that one dot represents according to some phenomena's distributed density.
The larger the dot shape is, the smaller of the dot value sets. The dot value too large or too small is not appropriate.
Methods
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SuperMap.ThemeDotDensity.fromObj(obj){SuperMap.ThemeDotDensity}
ThemeDotDensity.js, line 86 -
Getting the style of point density in the point density map from the incoming object.
Name Type Description objObject The incoming object
Returns:
Type Description SuperMap.ThemeDotDensity ThemeDotDensity object. -
destroy()
ThemeDotDensity.js, line 54 -
Disposes the resource. The property that references resource is set to null.
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toServerJSONObject(){Object}
ThemeDotDensity.js, line 70 -
Turned to the JSON format object.
Returns:
Type Description Object The JSON object.