Zusammenfassung
Scatter plots visualize the relationship between two numeric variables, where one variable is displayed on the x-axis, and the other variable is displayed on the y-axis. For each record, a point is plotted where the two variables intersect in the chart. When the resulting points form a nonrandom structure, a relationship exists between the two variables.
Diskussion
When creating a chart 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
Scatter (x, y, {sizeField}, {sizeMin}, {sizeMax}, {showTrendLine}, {title}, {description}, {xTitle}, {yTitle}, {dataSource}, {displaySize})| Parameter | Erläuterung | Datentyp |
x | The field name for the x-axis variable. The field must be a numeric field. | String |
y | The field name for the y-axis variable. The field must be a numeric field. | String |
sizeField | The field used to determine the size of the proportional symbol when creating a bubble plot. | String |
sizeMin | The minimum size for points in a bubble plot. | Integer |
sizeMax | The maximum size for points in a bubble plot. | Integer |
showTrendLine | Indicates whether the trend line is visible in the scatter plot. True displays the line. False hides the line. | Boolean |
title |
Sets 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 | Sets the description of the chart. The description text appears at the bottom of the chart view. | String |
xTitle | Sets the title for the x-axis of the chart. | String |
yTitle | Sets the title for the y-axis of the chart. | String |
dataSource | Sets the data source of the chart. When a chart is exported using the exportToSVG method or displayed in an ArcGIS Notebook, the data source is read and rendered on the chart. Valid data sources include paths to datasets, including local datasets, UNC paths, and service URLs, and arcpy.mp Layer objects. | Object |
displaySize [displaySize,...] | Sets 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, where the first item is the width of the chart and the second item is the height of the chart. | List |
Eigenschaften
| Eigenschaft | Erläuterung | Datentyp |
| dataSource (Lesen und schreiben) | Sets the data source of the chart. When a chart is exported using the exportToSVG method or displayed in an ArcGIS Notebook, the data source is read and rendered on the chart. Valid data sources include paths to datasets, including local datasets, UNC paths, and service URLs, and arcpy.mp Layer objects. | Object |
| description (Lesen und schreiben) | Sets the description of the chart. The description text appears at the bottom of the chart view. | String |
| displaySize (Lesen und schreiben) | Sets 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, where the first item is the width of the chart and the second item is the height of the chart. | List |
| legend (Lesen und schreiben) | Sets the properties of the chart legend.
| Object |
| sizeField (Lesen und schreiben) | The field used to determine the size of the proportional symbol when creating a bubble plot. | String |
| sizeMin (Lesen und schreiben) | The minimum size for points in a bubble plot. | Integer |
| sizeMax (Lesen und schreiben) | The maximum size for points in a bubble plot. | Integer |
| showTrendLine (Lesen und schreiben) | Indicates whether the trend line is visible in the scatter plot. True displays the line. False hides the line. | Boolean |
| title (Lesen und schreiben) | Sets 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 (Schreibgeschützt) | The string value indicating the chart type. | String |
| x (Lesen und schreiben) | The field name for the x-axis variable. The field must be a numeric field. | String |
| xAxis (Lesen und schreiben) | Sets the properties of the x-axis.
| Object |
| y (Lesen und schreiben) | The field name for the y-axis variable. The field must be a numeric field. | String |
| yAxis (Lesen und schreiben) | Sets the properties of the y-axis.
| Object |
.Methodenübersicht
| Methode | Erläuterung |
| addToLayer (layer_or_layerfile) | Adds the chart object to a layer or stand-alone table. |
| exportToSVG (path, width, height) | Exports the chart to SVG format. |
| updateChart () | Updates chart properties to sync changes between the object and the chart previously added to a layer. |
Methoden
addToLayer (layer_or_layerfile)
| Parameter | Erläuterung | Datentyp |
layer_or_layerfile | The chart will be added to the target object. The layer_or_layerfile argument can be a Layer or a Table object. | Object |
Often the final step after defining chart properties is to add the chart object to a layer or table using the addToLayer method.
Add a chart to an existing layer.
import arcpy
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 | Erläuterung | Datentyp |
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 a 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
aprx = arcpy.mp.ArcGISProject('current')
censusLayer = aprx.listMaps()[0].listLayers('Census Block Groups')[0]
# Set data source of chart object to a layer within 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.
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 ()
Often the final step after defining chart properties is to add the chart object to a layer using the addToLayer method.
To further modify the chart properties, you can modify the properties of the original chart instead of starting from scratch 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 will allow 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.
chart.addToLayer(myLayer)
# Further modification is necessary
chart.description = "Data from the U.S. Census Bureau"
chart.updateChart()Codebeispiel
Create a scatter plot and add it to a layer from the current project.
import arcpy
aprx = arcpy.mp.ArcGISProject("current")
map = aprx.listMaps()[0]
censusLayer = map.listLayers("Census Block Groups")[0]
chart = arcpy.charts.Scatter(x="Per_Vacant", y="Pop_Density", xTitle="Vacant Housing %",
yTitle="Population Density (per Sq. Mile)")
chart.addToLayer(censusLayer)