Bar

Summary

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 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 Samples section for an example of how to specify arguments using keywords.

Syntax

Bar (x, {y}, {aggregation}, {splitCategory}, {multiSeriesDisplay}, {miniChartsPerRow}, {showPreviewChart}, {showMovingAverage}, {movingAveragePeriod}, {timeBinningProperties}, {rotated}, {title}, {description}, {xTitle}, {yTitle}, {dataSource}, {displaySize})
ParameterExplanationData Type
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 that occur at the same value along the x-axis.

  • <None>Each value will be plotted on the chart regardless of overlap or recurring values.
  • COUNTThe total number of records will be identified and applied.
  • SUMThe sum of all values will be calculated and applied.
  • MEANThe mean of all values will be calculated and applied.
  • MEDIANThe median of all values will be identified and applied.
  • MINThe minimum value will be identified and applied.
  • MAXThe 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.

  • sideBySideThe series will be displayed side by side.
  • stackedThe series will be displayed stacked.
  • stacked100The series will be displayed 100 percent stacked.
  • gridThe series will be displayed as a grid of miniplots.
String
miniChartsPerRow

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
showPreviewChart

Specifies whether the preview chart will be displayed for grid charts.

  • TrueThe preview chart will be displayed.
  • FalseThe preview chart will not be displayed.

(The default value is False)

Boolean
showMovingAverage

Specifies whether the moving average line will be displayed for temporal bar charts.

  • TrueThe moving average line will be displayed.
  • FalseThe moving average line will be hidden.

(The default value is False)

Boolean
movingAveragePeriod

The size of the moving average period.

Integer
timeBinningProperties

The time binning properties from the TimeBinningProperties class.

Object
rotated

Specifies whether bars will be displayed vertically or horizontally.

  • TrueBars will be displayed horizontally.
  • FalseBars will be displayed vertically.

(The default value is 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 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
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

PropertyExplanationData Type
aggregation
(Read and Write)

Specifies the statistical calculation that is applied to values that occur at the same value along the x-axis.

  • <None>Each value is plotted on the chart regardless of overlap or recurring values.
  • COUNTThe total number of records is identified and applied.
  • SUMThe sum of all values is calculated and applied.
  • MEANThe mean of all values is calculated and applied.
  • MEDIANThe median of all values is identified and applied.
  • MINThe minimum value is identified and applied.
  • MAXThe maximum value is identified and applied.
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:

  • Paths to datasets, including local datasets, UNC paths, and service URLs
  • Arrow table objects
  • Layer or Table objects

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.

  • 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
(Read and Write)

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
(Read and Write)

The size of the moving average period.

Integer
multiSeriesDisplay
(Read and Write)

Specifies the display type for a bar chart with multiple series.

  • sideBySideThe series are displayed side by side.
  • stackedThe series are displayed stacked.
  • stacked100The series are displayed 100 percent stacked.
  • gridThe series are displayed as a grid of miniplots.
String
nullCategoryColor
(Read and Write)

The hexadecimal color value for the null category bar.

String
nullCategoryLabel
(Read and Write)

The x-axis label for the null category bar.

String
rotated
(Read and Write)

Specifies whether the chart will be displayed vertically or horizontally.

  • TrueThe chart will be displayed horizontally.
  • FalseThe chart will be displayed vertically.
Boolean
showMovingAverage
(Read and Write)

Specifies whether the moving average line is displayed for temporal bar charts.

  • TrueThe moving average line is displayed.
  • FalseThe moving average line is hidden.
Boolean
showNullCategory
(Read and Write)

Specifies whether null values are summarized by an additional bar.

  • TrueThe null category bar is displayed.
  • FalseThe null category bar is hidden.
Boolean
showPreviewChart
(Read and Write)

Specifies whether the preview chart will be displayed for grid charts.

  • TrueThe preview chart will be displayed.
  • FalseThe preview chart will not be displayed.
Boolean
splitCategory
(Read and Write)

A second categorical field that adds a separate series or bar for each unique value in the field.

String
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 List By Drawing Order.

String
timeBinningProperties
(Read and Write)

The time binning properties from the TimeBinningProperties class.

Object
type
(Read Only)

The string value indicating the chart type.

String
theme
(Read and Write)

The name of the theme that will be applied to the chart.

String
x
(Read and Write)

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
(Read and Write)

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
(Read and Write)

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
(Read and Write)

Sets 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.
  • 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.
  • 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

Method Overview

MethodExplanation
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)
ParameterExplanationData 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)
ParameterExplanationData 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 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()

Code sample

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)