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Line

In this topic

  1. Summary
  2. Discussion
  3. Syntax
  4. Properties
  5. Method Overview
  6. Methods
  7. Code sample

Summary

The Line class creates line charts. Line charts allow you to visualize change over a continuous range, such as time or distance. Visualizing change with a line chart allows for the overall trend to be displayed at once, and for multiple trends to be compared simultaneously.

Learn more about line charts in ArcGIS Pro

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

Line (x, {y}, {splitCategory}, {multiSeriesDisplay}, {miniChartsPerRow}, {showPreviewChart}, {aggregation}, {timeIntervalUnits}, {timeIntervalSize}, {timeAggregationType}, {trimIncompleteTimeInterval}, {nullPolicy}, {showMovingAverage}, {movingAveragePeriod}, {rotated}, {title}, {description}, {xTitle}, {yTitle}, {dataSource}, {displaySize}, {theme})
ParameterExplanationData Type
x

The field name for the x-axis variable. The field must be a numeric or date field.

String
y

The field name or names for the y-axis variables. The value must be a numeric field or a list of numeric fields.

String
splitCategory

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

String
multiSeriesDisplay

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

  • singleChart—All series will be displayed in a single chart.
  • 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.

(The default value is False)

Boolean
aggregation

Specifies the statistical calculation that will be applied to values aggregated into each temporal or numeric bin.

  • <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
timeIntervalUnits

Specifies the time unit that corresponds to the timeIntervalSize value.

  • SECONDS—The time unit will be seconds.
  • MINUTES—The time unit will be minutes.
  • HOURS—The time unit will be hours.
  • DAYS—The time unit will be days.
  • WEEKS—The time unit will be weeks.
  • MONTHS—The time unit will be months.
  • YEARS—The time unit will be years.
String
timeIntervalSize

The span of time that will be binned or aggregated together. This argument must be used in conjunction with timeIntervalUnits.

String
timeAggregationType

Specifies the time interval alignment type.

  • equalIntervalsFromStartTime—The time interval will be aligned to the start date.
  • equalIntervalsFromEndTime—The time interval will be aligned to the end date.
String
trimIncompleteTimeInterval

Specifies whether incomplete time intervals at the start or end of the data span (depending on the timeAggregationType value) will be removed (trimmed) from the chart. Incomplete intervals on a chart can cause misleading results in which the period in question is underreported or overreported due to a different amount of time in the interval.

  • True—Incomplete intervals will be removed.
  • False—Incomplete intervals will not be removed.
String
nullPolicy

Specifies how summarized bins returning a null value will be displayed.

  • null—Missing values will be treated as null.
  • zero—Missing values will be treated as zero.
  • interpolate—Interpolation will be used to fill missing values.
String
showMovingAverage

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

  • True—The moving average line will be displayed.
  • False—The moving average line will not be displayed; it will be hidden.

(The default value is False)

Boolean
movingAveragePeriod

The size of the moving average period.

Integer
rotated

Specifies whether lines will be displayed horizontally or vertically.

  • True—Lines will be displayed vertically.
  • False—Lines will be displayed horizontally.

(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 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

Properties

PropertyExplanationData Type
aggregation
(Read and Write)

Specifies the statistical calculation that will be applied to values aggregated into each temporal or numeric bin.

  • <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
color
(Read and Write)

The colors that will be applied to each chart series. The value should be a list of hexadecimal string values. If this property is not set, the series colors will match symbology colors where applicable; otherwise, a standard color palette will be applied.

List
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
  • Apache 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
enableServerSideProcessing
(Read and Write)

Specifies whether server-side processing will be used when data comes from an enterprise database or cloud data warehouse.

  • True—Server-side processing will be enabled.
  • False—Server-side processing will be disabled.
Boolean
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 mini charts that will be shown per row.

Integer
movingAveragePeriod
(Read and Write)

The size of the moving average period.

Integer
multiSeriesDisplay
(Read and Write)

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

  • singleChart—All series will be displayed in a single chart.
  • grid—The series will be displayed as a grid of mini charts.
String
nullPolicy
(Read and Write)

Specifies how summarized bins returning a null value will be displayed.

  • null—Missing values will be treated as null.
  • zero—Missing values will be treated as zero.
  • interpolate—Interpolation will be used to fill missing values.
String
rotated
(Read and Write)

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
showPreviewChart
(Read and Write)

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
(Read and Write)

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

String
theme
(Read and Write)

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
showMovingAverage
(Read and Write)

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

  • True—The moving average line will be displayed.
  • False—The moving average line will not be displayed; it will be hidden.
Boolean
timeAggregationType
(Read and Write)

Specifies the time interval alignment type.

  • equalIntervalsFromStartTime—The time interval will be aligned to the start date.
  • equalIntervalsFromEndTime—The time interval will be aligned to the end date.
String
timeIntervalSize
(Read and Write)

The span of time that will be binned or aggregated together. This property must be used in conjunction with timeIntervalUnits.

String
timeIntervalUnits
(Read and Write)

Specifies the time unit that corresponds to the timeIntervalSize value.

  • SECONDS—The time unit will be seconds.
  • MINUTES—The time unit will be minutes.
  • HOURS—The time unit will be hours.
  • DAYS—The time unit will be days.
  • WEEKS—The time unit will be weeks.
  • MONTHS—The time unit will be months.
  • YEARS—The time unit will be years.
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
trimIncompleteTimeInterval
(Read and Write)

Specifies whether incomplete time intervals at the start or end of the data span (depending on the timeAggregationType value) will be removed (trimmed) from the chart. Incomplete intervals on a chart can cause misleading results in which the period in question is underreported or overreported due to a different amount of time in the interval.

  • True—Incomplete intervals will be removed.
  • False—Incomplete intervals will not be removed.
String
type
(Read Only)

The string value indicating the chart type.

String
x
(Read and Write)

The field name for the x-axis variable. The field must be a numeric or date field.

String
xAxis
(Read and Write)

Specifies the properties of the x-axis.

  • addGuide—Adds a guide to the axis using a Guide object.
  • field—The field name for the x-axis variable. The field must be a numeric or date field.
  • logarithmic—Specifies whether the axis is logarithmic. True displays the logarithmic axis. False displays the linear axis.
  • 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—This property is not supported for the Line class.
  • title—The label of the axis that displays on the chart.
Object
y
(Read and Write)

The field name or names for the y-axis variables. The value must be a numeric field or a list of numeric fields.

String
yAxis
(Read and Write)

Specifies the properties of the y-axis.

  • addGuide—Adds a guide to the axis using a Guide object.
  • field—The field name or names y-axis variables. Provide a single numeric field or a list of numeric fields.
  • invert—Specifies whether the axis is inverted. True inverts the axis, and False does not invert the axis.
  • logarithmic—Specifies whether the axis is logarithmic. True displays the logarithmic axis. False displays the linear axis.
  • 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—This property is not supported for the Line class.
  • 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.

exportToJPEG (path, width, height)

The exportToJPEG method exports a chart to JPEG format.

exportToPNG (path, width, height)

The exportToPNG method exports a chart to PNG format.

exportToSVG (path, width, height)

The exportToSVG method exports a 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)
exportToJPEG (path, width, height)
ParameterExplanationData Type
path

The path where the chart will be exported in JPEG format.

String
width

The width of the output graphic.

Integer
height

The height of the output graphic.

Integer

The chart is exported to a .jpg file that can be shared and viewed outside of ArcGIS Pro. JPEG is a raster image format that uses lossy compression to reduce file size.

Export a chart that has a feature service data source to a .jpeg 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.exportToJPEG('theftsPerBeat.jpg', 800, 600)
exportToPNG (path, width, height)
ParameterExplanationData Type
path

The path where the chart will be exported in PNG format.

String
width

The width of the output graphic.

Integer
height

The height of the output graphic.

Integer

The chart is exported to a .png file that can be shared and viewed outside of ArcGIS Pro. PNG is a raster image format that uses lossless compression to preserve image quality.

Access an existing chart from a layer, update the title, and export it to a .png file.

import arcpy

lyr = arcpy.mp.ArcGISProject('current').listLayers()[0]

# Retrieve the first chart belonging to the layer
chart = lyr.listCharts()[0]

# Update chart title
chart.title = 'Voter Turnout by State'

# Save the chart to PNG file with dimensions width=800, height=600
chart.exportToPNG('populationByState.png', 800, 600)
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

The chart is exported to an .svg file that can be shared and viewed outside of ArcGIS Pro. SVG is a vector image format that allows for editing and infinite scaling of the graphic without a 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)
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 line chart and add it to a layer in the current project.

import arcpy

lyr = arcpy.mp.ArcGISProject("current").listMaps()[0].listLayers()[0]
chart = arcpy.charts.Line(x="date", y="aqi", aggregation="mean")
chart.addToLayer(lyr)

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In this topic
  1. Summary
  2. Discussion
  3. Syntax
  4. Properties
  5. Method Overview
  6. Methods
  7. Code sample