NB. Interpolation. No extrapolation. X=. 0 5 6 26
X0=.}:X X1=.}.X Y=. 10 _10 80 100 Y0=.}:Y Y1=.}.Y H=.(Y1-Y0)%(X1-X0) f=. 3 : '+/(X0<:/y)*(X1>/y)*Y0+H*X0-~/y' f 0 5 10 15 20 25 10 _10 84 89 94 99 ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
