Trading system toolbox
|SYNTAX||Ref( ARRAY, period )|
|FUNCTION||References a previous or subsequent element in a ARRAY. A positive period references "n" periods in the future; a negative period references "n" periods ago. The function accepts periods parameter that can be constant as well as time-variant (array).|
|EXAMPLE||The formula "ref( CLOSE, -14 )" returns the closing price 14 periods ago. Thus, you could write the 14-day price rate-of-change (expressed in points) as "C - ref( C, -14 )." The formula "ref( C, 12 )" returns the closing price 12 periods ahead (this means looking up the future)|
The Ref function is used in the following formulas in AFL on-line library:
See updated/extended version on-line.