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Similar to format-number-hash for form #formatNumber.{form.table.field}[decimal=2], you can use a similar approach to formatting numbers retrieved from a datalist. When you have a hash variable that holds the sum or any numerical data from a datalist, you can format this number by placing it inside the format-number-hash syntax. This allows you to specify the desired number of decimal places or other formatting options.
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If you are performing arithmetic operations on data from datalists and wish to apply number formatting to the aggregated total, you can employ a nested expression hash variable. This would involve summing up the columns and then formatting the resulting total with the format-number-hash. To learn more about using dynamic hash variable values within information tiles, please refer to the relevant documentation page use dynamic hash variable values inside information tiles
If you want to have the number formatted on the total value, The hash variable expression for that would be:
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Figure 3: Formatting the total value
know more at Hash Variable, under the Expression Hash Variable (New) section, on how to use different expressions.
Also, refer to the Format Number Hash Plugin, to learn how to format numbers.