Hi, In my program I have many points in a two-dimensional space, let's say on the X-axis I have time and on the Y-axis I have values ranging from -100 to +100. But unfortunately not for every value on the X-axis I have a Y-value. Though, I have to be able to "guess" the Y-values for every X-value. The (x,y)-points do correlate but I do not now how; sometimes it is a straight line, other times it is parabolic. My question is if boost has any support for this kind of problem. Thank you, Andrej