Bar

Synthèse

The Bar class creates bar charts. Bar charts summarize and compare categorical data using proportional bar lengths to represent values.

Learn more about bar charts in ArcGIS AllSource

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.

Syntaxe

Bar (x, {y}, {aggregation}, {splitCategory}, {multiSeriesDisplay}, {miniChartsPerRow}, {showPreviewChart}, {showMovingAverage}, {movingAveragePeriod}, {timeBinningProperties}, {rotated}, {title}, {description}, {xTitle}, {yTitle}, {dataSource}, {displaySize}, {theme})

Paramètre	Explication	Type de données
x	The field name for the x-axis variable. The field must be a category or a date field. If an empty string is specified, the chart will match the layer symbology.	String
y	The field names for the numeric fields. Provide a single field name or a list of field names.	String
aggregation	Specifies the statistical calculation that will be applied to values aggregated into each bar. <None>—Each value will be plotted on the chart regardless of overlap or recurring values. COUNT—The total number of records will be identified and applied. SUM—The sum of all values will be calculated and applied. MEAN—The mean of all values will be calculated and applied. MEDIAN—The median of all values will be identified and applied. MIN—The minimum value will be identified and applied. MAX—The maximum value will be identified and applied.	String
splitCategory	A second categorical field that adds a separate series or bar for each unique value in the field.	String
multiSeriesDisplay	Specifies the display type for a bar chart with multiple series. sideBySide—The series will be displayed side by side. stacked—The series will be displayed stacked. stacked100—The series will be displayed 100 percent stacked. grid—The series will be displayed as a grid of mini charts.	String
miniChartsPerRow	The number of mini charts that will be shown per row.	Integer
showPreviewChart	Specifies whether the preview chart will be displayed for grid charts. True—The preview chart will be displayed. False—The preview chart will not be displayed. (La valeur par défaut est False)	Boolean
showMovingAverage	Specifies whether the moving average line will be displayed for temporal bar charts. True—The moving average line will be displayed. False—The moving average line will be hidden. (La valeur par défaut est False)	Boolean
movingAveragePeriod	The size of the moving average period.	Integer
timeBinningProperties	The time binning properties applied to temporal bar charts. Expects a TimeBinningProperties object.	Object
rotated	Specifies whether bars will be displayed vertically or horizontally. True—Bars will be displayed horizontally. False—Bars will be displayed vertically. (La valeur par défaut est False)	Boolean
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 ArcGIS Notebooks, the data source will be read and rendered on the chart. Valid data sources include the following: Paths to datasets, including local datasets, UNC paths, and service URLs Apache Arrow table objects Layer or Table objects	Object
displaySize [displaySize,...]	The size of the chart when exported using the exportToSVG method or displayed in ArcGIS Notebooks. 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
theme	Specifies the theme that will be applied to the chart. Light—The Light theme will be applied. Medium—The Medium theme will be applied. Dark—The Dark theme will be applied.	String

Propriétés

Propriété	Explication	Type de données
aggregation (Lecture et écriture)	Specifies the statistical calculation that will be applied to values aggregated into each bar. <None>—Each value will be plotted on the chart regardless of overlap or recurring values. COUNT—The total number of records will be identified and applied. SUM—The sum of all values will be calculated and applied. MEAN—The mean of all values will be calculated and applied. MEDIAN—The median of all values will be identified and applied. MIN—The minimum value will be identified and applied. MAX—The maximum value will be identified and applied.	String
MISSING_PROPNAME (Lecture et écriture)		List
dataSource (Lecture et écriture)	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: Paths to datasets, including local datasets, UNC paths, and service URLs Arrow table objects Layer or Table objects	Object
description (Lecture et écriture)	The description of the chart. The description text appears at the bottom of the chart view.	String
displaySize (Lecture et écriture)	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
MISSING_PROPNAME (Lecture et écriture)		Boolean
legend (Lecture et écriture)	The properties of the chart legend. alignment—Specifies the alignment of the legend. Alignment options are left, bottom, top, and right. title—The title of the legend. visible—Specifies whether the legend will be displayed in the chart view. True displays the legend, and False hides the legend.	Object
miniChartsPerRow (Lecture et écriture)	The number of minicharts that will be shown per row. The number of rows will be determined by the total number of series divided by the miniChartsPerRow value.	Integer
movingAveragePeriod (Lecture et écriture)	The size of the moving average period.	Integer
multiSeriesDisplay (Lecture et écriture)	Specifies the display type that will be used for a bar chart with multiple series. sideBySide—The series will be displayed side by side. stacked—The series will be displayed stacked. stacked100—The series will be displayed 100 percent stacked. grid—The series will be displayed as a grid of mini charts.	String
nullCategoryColor (Lecture et écriture)	The hexadecimal color value for the null category bar.	String
nullCategoryLabel (Lecture et écriture)	The x-axis label for the null category bar.	String
rotated (Lecture et écriture)	Specifies whether the chart will be displayed vertically or horizontally. True—The chart will be displayed horizontally. False—The chart will be displayed vertically.	Boolean
showMovingAverage (Lecture et écriture)	Specifies whether the moving average line will be displayed for temporal bar charts. True—The moving average line will be displayed. False—The moving average line will be hidden.	Boolean
showNullCategory (Lecture et écriture)	Specifies whether null values will be summarized by an additional bar. True—The null category bar will be displayed. False—The null category bar will be hidden.	Boolean
showPreviewChart (Lecture et écriture)	Specifies whether the preview chart will be displayed for grid charts. True—The preview chart will be displayed. False—The preview chart will not be displayed.	Boolean
splitCategory (Lecture et écriture)	A second categorical field that adds a separate series or bar for each unique value in the field.	String
title (Lecture et écriture)	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
timeBinningProperties (Lecture et écriture)	The time binning properties that will be applied to temporal bar charts. The value must be a TimeBinningProperties object.	Object
type (Lecture seule)	The string value indicating the chart type.	String
theme (Lecture et écriture)	The name of the theme that will be applied to the chart.	String
x (Lecture et écriture)	The field name for the x-axis variable. The field must be a category or a date field. If an empty string is specified, the chart will match the layer symbology.	String
xAxis (Lecture et écriture)	Sets the properties of the x-axis. field—The field name for the x-axis variable. The field must be a category or a date field. logarithmic—This property is not supported for the Bar class. maximum—The maximum axis bound. minimum—The minimum axis bound. sort—Specifies the sorting method applied to this axis. ASC is for ascending sorting and DESC is for descending sorting. A custom sort order can be specified by assigning a list of ordered category names. title—The label of the axis that displays on the chart. useAdaptiveBounds—Specifies whether a grid chart displays with adaptive or fixed axis bounds. True displays the axis with adaptive bounds. False displays the axis with fixed bounds.	Object
y (Lecture et écriture)	The field name or names for the numeric field or fields. This property must specify a single field name or a list of field names.	String
yAxis (Lecture et écriture)	Specifies the properties of the y-axis. addGuide—Adds a guide to the axis using a Guide object. field—The field name or names for the numeric field or fields. This property must specify a single field name or a list of field names. logarithmic—This property is not supported for the Bar class. listGuides—A list of Guide objects for the axis. maximum—The maximum axis bound. minimum—The minimum axis bound. removeGuide—Removes the guide specified by the Guide object argument. sort—Specifies the sorting method applied to this axis. ASC is for ascending sorting and DESC is for descending sorting. title—The label of the axis that displays on the chart. useAdaptiveBounds—Specifies whether a grid chart displays with adaptive or fixed axis bounds. True displays the axis with adaptive bounds. False displays the axis with fixed bounds.	Object

Vue d’ensemble des méthodes

Méthode	Explication
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.

Méthodes

addToLayer (layer_or_layerfile)

Paramètre	Explication	Type de données
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)

Paramètre	Explication	Type de données
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 AllSource. 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()

Exemple de code

Create a bar chart using a feature service and export the chart to an .svg file.

import arcpy

url = r"https://services1.arcgis.com/hLJbHVT9ZrDIzK0I/arcgis/rest/services/CrimesChiTheft/FeatureServer/0"
chart = arcpy.charts.Bar(x="BEAT", aggregation="count", title="Chicago Thefts by Beat", dataSource=url)
chart.exportToSVG('bar.svg', width=800, height=500)