abc calculates the top A%, next B%, and remaining C% of a measure as divided by a particular grouping.
abc([Quantity], .8, .95, 1)
would calculate the top 80% of quantity values in the report as class A, the next 15% as B, and the remaining 5% as C.
datefilterstartvalue returns the start date of the specified date filter.
datefilterstartvalue("Filter Name")
would return the start date of the filter matching to Filter Name.
datefilterstartvalue returns the end date of the specified date filter.
datefilterstartvalue("Filter Name")
would return the end date of the filter matching to Filter Name.
fieldchoice returns the field selected by the specified field choice filter.
fieldchoice([Metric])
looks for the field selected in the Metric field choice filter.
As an example of where you might use this function, you could do a Numerator as one field choice and a Denominator as a second, with a calculation of:
fieldchoice([Numerator]) / fieldchoice([Denominator])
