React PolarChart - series.valueErrorBar

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 a measurement is.

In PolarChart, an error bar is a vertical bar with two marks at its edges. An error bar accompanies a series point. 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 properties.

Alternatively, you can calculate the high and low error bar values automatically. For this purpose, choose one of error bar types and specify the value to be used in calculation.

This property supports the following colors:

• Hexadecimal colors
• RGB colors
• RGBA colors
• Predefined/cross-browser color names
• Predefined SVG colors
• Paint server address

Usually, when displaying error bars, you need both the lower and higher parts of them to indicate the error. This case corresponds to the displayMode property equaling 'auto'. If you need to display the lower or higher parts separately, set this property to 'low' or 'high' respectively. To hide error bars, assign 'none' to this property.

Use the ValueErrorBarDisplayMode enum to specify this property when the UI component is used as an ASP.NET MVC 5 Control or a DevExtreme-Based ASP.NET Core Control. This enum accepts the following values: Auto, Low, High, and None.

A value in the range from 0 to 1 specifies the length relative to the point diameter (for circular series points) or angular width (for bars).

Any other value specifies the length in pixels.

If you need to generate error bars from concrete values, specify the highValueField property with the name of the field that provides them. These values will be displayed on a chart as the higher end of error bars. To provide data for the lower end of error bars, specify the lowValueField property.

If you need to generate error bars from concrete values, specify the lowValueField property with the name of the field that provides them. These values will be displayed on a chart as the lower end of error bars. To provide data for the higher end of error bars, specify the highValueField property.

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

• 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 property. 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 property. The high and low error bar values are drawn symmetrically up and down from the series point.

Use the ValueErrorBarType enum to specify this property when the UI component is used as an ASP.NET MVC 5 Control or a DevExtreme-Based ASP.NET Core Control. This enum accepts the following values: Percent, StdError, StdDeviation, Variance, and Fixed.

Depending on the value of the type property, the value property is applied as follows.

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

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

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

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

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