If the data values are beyond the numeric ranges defined in the colorRange object, the chart will show blank data plots. For example, the numeric range defined is 0-30, 30-70 and 70-100 and in the data object there are values such as -10 and 123. The chart will display all the data values within the range but will show blank data plots in place of -10 and 123.
A chart with a blank data plot rendered for out-of-range data looks like this:
In the above chart, the cells that represent the job happiness index for the accounting department at Compton-Rancho Dom and the marketing department at Garden Groove Harbour are blank.
The data structure needed to create the above heat map chart is given below:
Look at the data structure. The data values specified for the accounting department at Compton-Rancho Dom and the marketing department at Garden Groove Harbour fall outside the defined range.
To avoid such blank data plots, you can enable percentage mapping for heat map charts.
Using Percentage Mapping to Handle Out-of-range Data
Percentage mapping is a feature that allows the chart to display the data values in percentage.
A heat map chart with percentage mapping looks like this:
Given below is a brief description of the attribute used to enable percentage mapping:
| Attribute Name | Description |
|---|---|
mapByPercent |
It is used to specify whether percentage mapping will be enabled for heat map charts. Setting this attribute to 1 will enable percentage mapping, setting it to 0 (default) will disable it. This attribute is used with the colorRange object. |
When percentage mapping is used, the lowest data value from the JSON data is considered to be the lower limit and will be displayed as 0%; the highest data value is considered as the upper limit and will be displayed as 100%. Color ranges have to be created with 0 as the lower limit and 100 as the upper limit.
The data structure needed to enable percentage mapping is given below:
You can choose to enable percentage mapping even when all your data values fall within the defined range.
In category based heat map chart, if you provide a category name by the attribute colorRangeLabel through the data element which is not defined in the colorRange element, the chart will show blank dataplot.