valueErrorBar

Configures error bars.

Type:

Object

This member is exposed by the following entities:

Error bars are used on charts to indicate an error or an uncertainty in a reported measurement. They give a general idea of how precise the measurement is.

DevExtreme HTML5 Charts ErrorBars

Error bars can be generated either from concrete or calculated values. To generate one error bar, two values, high and low, are needed. If the data source of your chart provides concrete high and low values, assign the required data source fields to the highValueField and lowValueField options.

Alternatively, the error bar values can be calculated according to an algorithm. In this case, choose the needed algorithm using the type option, and specify the value to be used in calculation using the value option.

NOTE
Error bars are available for axes of the numeric type only.

View Demo

color

Specifies the color of error bars.

Type:

String

Default Value: 'black'

This option supports the following colors.

displayMode

Specifies whether error bars must be displayed in full or partially.

Type:

String

Default Value: 'auto'
Accepted Values: 'auto' | 'low' | 'high' | 'none'

This option accepts the following values.

displayMode Result
"auto" Displays error bars in full.
"low" Displays only the lower part of each error bar.
"high" Displays only the higher part of each error bar.
"none" Hides error bars.

When configuring the widget using ASP.NET MVC Wrappers, specify this option using the ValueErrorBarDisplayMode enum. This enum accepts the following values: Auto, Low, High and None.

edgeLength

Specifies the length of the lines that indicate the error bar edges.

Type:

Number

Default Value: 8

highValueField

Specifies which data field provides high error values.

Type:

String

Default Value: undefined
NOTE
If you are using the highValueField option, do not specify the valueErrorBar | type option.

lineWidth

Specifies the width of the error bar line.

Type:

Number

Default Value: 2

lowValueField

Specifies which data field provides low error values.

Type:

String

Default Value: undefined
NOTE
If you are using the lowValueField option, do not specify the valueErrorBar | type option.

opacity

Specifies how trasparent error bars should be.

Type:

Number

Default Value: undefined

This option accepts a value from 0 to 1, where 0 makes error bars completely transparent, and 1 makes them opaque.

type

Specifies how error bar values must be calculated.

Type:

String

Default Value: undefined
Accepted Values: 'percent' | 'stdError' | 'stdDeviation' | 'variance' | 'fixed'

Depending on the type of errors you need to visualize, use error bars of one of the following types.

type Description
"percent" Defines the confidential interval in percentages. Error bar values are calculated as a percentage of the series point value. The percentage value is determined by the value option. The high and low error bar values are drawn symmetrically up and down from the series point.
"stdError" For information on the standard error, refer to the article in Wikipedia.
"stdDeviation" For information on the standard deviation, refer to the article in Wikipedia.
"variance" For information on variance, refer to the article in Wikipedia.
"fixed" Defines the confidential interval in constant values. Error bar values are determined by the value option. The high and low error bar values are drawn symmetrically up and down from the series point.

When configuring the widget using ASP.NET MVC Wrappers, specify this option using the ValueErrorBarType enum. This enum accepts the following values: Percent, StdError, StdDeviation, Variance and Fixed.

value

Specifies the value to be used for generating error bars.

Type:

Number

Default Value: 1

Depending on the value of the type option, the value option applies as follows.

  • type: 'percent'
    The value option specifies the percentage of the series point value to be taken.

  • type: 'stdError'
    The value option multiplies the calculated standard error.

  • type: 'stdDeviation'
    The value option multiplies the calculated standard deviation.

  • type: 'variance'
    The value option multiplies the calculated variance.

  • type: 'fixed'
    The value option specifies constant error bar values.