Summary
The MatrixHeat class creates matrix heat charts. Matrix heat charts analyze relationships between two categorical fields, which can be visualized by count or summarized by a numeric field.
Discussion
When creating this object, optional arguments for the class constructor must be specified using the argument name; they cannot be specified by argument position. See the Code sample section for an example of how to specify arguments using keywords.
Syntax
MatrixHeat (x, y, {numberField}, {aggregation}, {nullPolicy}, {classificationMethod}, {classCount}, {timeBinningPropertiesCol}, {timeBinningPropertiesRow}, {title}, {description}, {xTitle}, {yTitle}, {dataSource}, {displaySize})
Parameter | Explanation | Data Type |
x | The name of the field that determines the column categories. | String |
y | The name of the field that determines the row categories. | String |
numberField | The name of the field that is aggregated and used to determine the color of the chart cells. | String |
aggregation | Specifies the statistical calculation that will be applied to values aggregated into each cell.
| String |
nullPolicy | Specifies how summarized cells returning a null value will be displayed.
| String |
classificationMethod | Specifies the classification method that will be used to visualize cell color and classify data.
| String |
classCount | The number of classes used in the classification method. | Integer |
timeBinningPropertiesCol | The time binning properties from the TimeBinningProperties class that are applied to the x-axis. | Object |
timeBinningPropertiesRow | The time binning properties from the TimeBinningProperties class that are applied to the y-axis. | Object |
title |
The title of the chart. The title text appears at the top of the chart view and is used as the label for the chart in the Contents pane. | String |
description | The description of the chart. The description text appears at the bottom of the chart view. | String |
xTitle | The title of the x-axis of the chart. | String |
yTitle | The title of the y-axis of the chart. | String |
dataSource | The data source of the chart. When a chart is exported using the exportToSVG method or displayed in an ArcGIS Notebook, the data source will be read and rendered on the chart. Valid data sources include the following: | Object |
displaySize [displaySize,...] | The size of the chart when exported using the exportToSVG method or displayed in an ArcGIS Notebook. The value must be specified as a two-item list in which the first item is the width of the chart and the second item is the height of the chart. | List |
Properties
Property | Explanation | Data Type |
aggregation (Read and Write) | Specifies the statistical calculation that will be applied to values aggregated into each cell.
| String |
classCount (Read and Write) | The number of classes used in the classification method. | Integer |
classificationMethod (Read and Write) | Specifies the classification method that will be used to visualize cell color and classify data.
| String |
dataSource (Read and Write) | The data source of the chart. When a chart is exported using the exportToSVG method or displayed in an ArcGIS notebook, the data source will be read and rendered on the chart. Valid data sources include the following: | Object |
description (Read and Write) | The description of the chart. The description text appears at the bottom of the chart view. | String |
displaySize (Read and Write) | The size of the chart when exported using the exportToSVG method or displayed in an ArcGIS notebook. The value must be specified as a two-item list in which the first item is the width of the chart and the second item is the height of the chart. | List |
legend (Read and Write) | The properties of the chart legend.
| Object |
nullPolicy (Read and Write) | Specifies how summarized cells returning a null value will be displayed.
| String |
numberField (Read and Write) | The name of the field that is aggregated and used to determine the color of the chart cells. | String |
theme (Read and Write) | The name of the theme that will be applied to the chart. | String |
timeBinningPropertiesCol (Read and Write) | The time binning properties from the TimeBinningProperties class that are applied to the x-axis. | Object |
timeBinningPropertiesRow (Read and Write) | The time binning properties from the TimeBinningProperties class that are applied to the y-axis. | Object |
title (Read and Write) | The title of the chart. The title text appears at the top of the chart view and is used as the label in the Contents pane on the List By Drawing Order tab . | String |
type (Read Only) | The string value indicating the chart type. | String |
x (Read and Write) | The name of the field that determines the column categories. | String |
xAxis (Read and Write) | The properties of the x-axis.
| Object |
y (Read and Write) | The name of the field that determines the row categories. | String |
yAxis (Read and Write) | The properties of the y-axis.
| Object |
Method Overview
Method | Explanation |
addToLayer (layer_or_layerfile) | The addToLayer method adds the chart object to a layer or table view. |
exportToSVG (path, width, height) | The exportToSVG method exports the chart to SVG format. |
updateChart () | The updateChart method updates chart properties to sync changes between the object and the chart previously added to a layer. |
Methods
addToLayer (layer_or_layerfile)
Parameter | Explanation | Data Type |
layer_or_layerfile | The chart will be added to the target object. This argument can be a Layer or Table object. | Object |
Adding the chart object to a layer or table using the addToLayer method is often the final step after defining chart properties.
Add a chart to an existing layer.
import arcpy
# Insert creation of chart object here
...
aprx = arcpy.mp.ArcGISProject("current")
map = aprx.listMaps()[0]
censusLayer = map.listLayers('Census Block Groups')[0]
# Add chart object to a layer
chart.addToLayer(censusLayer)
exportToSVG (path, width, height)
Parameter | Explanation | Data Type |
path | The path where the chart will be exported in SVG format. | String |
width | The width of the output graphic. | Integer |
height | The height of the output graphic. | Integer |
In some cases, you may want to save the chart as a graphic that can be shared and viewed outside of ArcGIS Pro. Exporting to the SVG graphic format is beneficial, as the chart elements and text are stored as vector elements that can be independently modified in vector graphics software. An SVG graphic can also be resized to any scale without pixelation or loss in quality.
Export a chart that has a project layer data source to an .svg file.
import arcpy
# Insert creation of chart object here
...
aprx = arcpy.mp.ArcGISProject('current')
censusLayer = aprx.listMaps()[0].listLayers('Census Block Groups')[0]
# Set data source of chart object to a layer in current project
chart.dataSource = censusLayer
# Save the chart to file with dimensions width=500, height=500
chart.exportToSVG('populationByState.svg', 500, 500)
Export a chart that has a feature service data source to an .svg file.
import arcpy
# Insert creation of chart object here
...
featureServiceURL = r'https://services1.arcgis.com/hLJbHVT9ZrDIzK0I/arcgis/rest/services/CrimesChiTheft/FeatureServer/0'
# Set data source of chart object to a feature service URL
chart.dataSource = featureServiceURL
# Save the chart to file with dimensions width=800, height=600
chart.exportToSVG('theftsPerBeat.svg', 800, 600)
updateChart ()
Adding the chart object to a layer using the addToLayer method is often the final step after defining chart properties.
You can also modify the properties of the original chart instead of starting with a new chart. You can then use the updateChart method to synchronize any changes into the chart that was added to the layer. This allows the changes you make to be presented in the Chart properties pane and chart view.
Use the updateChart method to synchronize chart property changes into a layer.
import arcpy
# Insert creation of chart object here
...
chart.addToLayer(myLayer)
# Further modification is necessary
chart.description = "Data from the U.S. Census Bureau"
chart.updateChart()
Code sample
Create a matrix heat chart using a .csv file and export the chart to an .svg file.
import arcpy
chart = arcpy.charts.MatrixHeat(x="OrigCity", y="DestCity", numberField="DelayTime",
aggregation="mean", title="Average Flight Arrival Delay",
displaySize=(800, 500), dataSource="flight_delays.csv")
chart.exportToSVG("matrix_heat_chart.svg")