Since my field to measure recency is not a date field but a string field (with only year-numbers in it), I tried a variation on the suggested boost function for recent documents: recip(sub(2015,min(sortyear,2015)),1,10,10) But this gives an exception when used in a boost or bf parameter. I guess the reason is that all the mathematics doesn't work with a string field even if it only contains numbers. Am I right with this guess? And if so, is there a function I can use to change the type to something numeric? Or are there other problems with my function?
Another related question: as you can see the current year (2015) is hard coded. Is there an easy way to get the current year within the function? Messing around with NOW looks very complicated. -Michael
