There are some methods to do curve fitting using linear and non-linear methods. These methods approximate data points by a function. but how can we approximate our data points by using multiple functions which are continuous at junctions?
My data-set has a decreasing trend. I need to approximate it by using two reciprocal functions, f1(x) [x form 'a' to 'b'] and f2(x) [x from 'b' to 'c'], and Also I need C1 or C2 Continuity at b. Is there any hope?
Also i don`t want to use B-Spline because i need Ordinary Least Square instead of Total Least Square.