Server Administration > Calculations in Fields, Charts, and Reports > Using Computed Fields to Chart Historical Trends > To calculate a computed field within a specific time frame
 
To calculate a computed field within a specific time frame
1. From a command line, type:
im analytics --recomputehistory -g
The Recompute Expression History For Field dialog box displays.
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If you are changing the value of Store to History Frequency from never to any other value, you may need to execute Analytics - Recompute Expression History for this field to display the correct computed value in the corresponding documents in multi-edit document view. Additionally, the start time for such re-computation must be equal to or earlier to the time when the computation field was last modified and the value of Store to History Frequency changed to never. If the computation field was created with the value of Store to History Frequency as never, then the start time for re-computation must be the same as the field creation time.
2. Select the following:
From the Field to Compute list, select the computed field that you want to calculate.
From the Start Time calendar, specify the starting calculation date and time.
From the End Time calendar, specify the ending calculation date and time.
From the Increment field, specify the interval to use for calculating the computed field. For example, if you select 1Week, the computed field is calculated once a week.
To clear previous history entries for the selected field between the specified times, select the Clear previous history option.
3. To calculate the computed field, click OK. Integrity Lifecycle Manager calculates the compute field, storing the value in the history of the each item containing the computed field.