Clears trend cache and delete trend file associated with specified trend.
This function needs to be called before a new variable can be assigned to a Instant Trend tag. This needs to be done as the trend tag may have been previously assigned to a different variable, in which case scrolling back through the trends history could display data not associated with the current variable.
Note: This function is to be called only on a Trends Server. To maintain redundancy the function is also called with the same arguments on the second/redundant Trends Server.
Number of Instant Trend to be cleared.