<data>

The <data> element provides the ability to select data sources for a chart to define series data, labels, or other chart elements.

A single <data> element is used to define a single series of data in a chart. For charts with multiple series, multiple <data> elements can be used, one element for each series in the chart. <data> elements must be contained by a <chart> element.

Syntax

<dynamic>
  <widget class_="graphics"> 
    [1010data_QUERY] 
      <graphspec> 
        <chart> 
          <data x="" y=""/> 
          <legend/> 
          <axes/> 
          <ticks/> 
          <style/>
        </chart> 
    </graphspec> 
  </widget> 
</dynamic>

The [1010data_QUERY] may be specified between the opening and closing tags of the <widget>. The results of the query provide data for the <widget> to display.

Attributes

x
The x attribute specifies the data that is typically used as the x-axis of the chart.

For pie charts, x is used to specify the labels that will appear that are not sections of the pie chart. For bar charts the attribute is used to produce that labels that are rendered next to each bar. Valid values are column names of columns containing numeric or text values. Exact uses of x are chart-type-dependent. If no value or an unknown value is provided, then a synthetic row count column is used or an appropriate error message is displayed.

y
The y attribute specifies the data that is typically used as the y-axis of the chart.

Valid values are column names of columns containing numeric or text values. Exact uses of y are chart-type-dependent. If no value or an unknown value is provided, then a synthetic row count column is used or an appropriate error message is displayed.

yaxis
When multiple data tags are specified when using multiple y-axes, yaxis specifies which of the two y-axes should be handle by the chart as the "secondary" y-axis. To specify that which y-axis series should be considered "secondary" in a <data> element, use: yaxis="s".

If yaxis="s", the as attribute can be used to specify that the second y-axis should be rendered as bars, not a line, using as="bar".

z
The z attribute specifies a data source of the chart and usually corresponds to data that is plotted on the z-axis.

z can also be used to specify other chart-specific characteristics. For bubble charts, the attribute is used to specify the size of each bubble (i.e., the size of a bubble corresponds to the specific value in a column of valid values for z). For surface charts, the attribute is used to specify the height of a surface.

Valid values are column names containing text or numerical data. If no or an unknown value is specified for z, then an appropriate error message is displayed.

yo
The yo attribute specifies a data source of a Candlestick chart, and usually corresponds to a price column.

Valid values are column names of columns containing numeric data most commonly corresponding to "open" prices.

If no or an unknown value is specified for yo then an appropriate error message is displayed.

yh
The yh attribute specifies a data source of a Candlestick chart, and usually corresponds to a price column.

Valid values are column names of columns containing numeric data most commonly corresponding to "high" prices.

If no or an unknown value is specified for yh then an appropriate error message is displayed.

yl
The yl attribute specifies a data source of a Candlestick chart, and usually corresponds to a price column.

Valid values are column names of columns containing numeric data most commonly corresponding to "low" prices.

If no or an unknown value is specified for yo then an appropriate error message is displayed.

yc
The yc attribute specifies a data source of a Candlestick chart, and usually corresponds to a price column.

Valid values are column names of columns containing numeric data most commonly corresponding to "close" prices.

If no or an unknown value is specified for yc then an appropriate error message is displayed.

label
The label attribute specifies a data series label. Such labels appear in legend entries.

Valid values are strings.

If no value or an unknown value for label is provided, then column names are used as the default.

groupby
The groupby attribute allows for specifying a column to aggregate data before the data is plotted.
Chart types that support groupby are as follows:
  • boxwhisker
  • line
  • scatter
  • line2d
  • scatter2d

Example: Bar Chart

This example creates a simple bar chart showing sales totals for three stores.

<dynamic>
  <widget class_="graphics" base_="pub.demo.retail.item" 
   width_="600" height_="400">
    <tabu label="Tabulation on Sales Item Detail" breaks="store">
      <tcol source="sales" fun="sum" label="Sum of`Sales"/>
    </tabu>
    <graphspec width="600" height="400">
      <chart type="bar" title="Sales by Store" samples="25">
        <data x="store" y="t0"/>
        <legend hide="0"/>
        <axes xlabel="Store" ylabel="Sales"/>
        <ticks xrot="25"/>
        <style titlesize="36" bg="lightblue"/>
      </chart>
    </graphspec>
  </widget>
</dynamic>