1. The problem statement, all variables and given/known data I have the following data which I would like to model using an exponential function of the form y = A + Becx. Using wolfram mathematica, solving for these coefficients was computed easily using the findfit function. I was tasked however to implement this using java and have come to this forum for help. Data X Y 10 88.822 20 45.607 30 26.407 40 18.004 50 12.504 60 10.878 70 8.229 80 8.032 90 6.674 100 6.927 110 6.146 120 6.18 130 6.19 140 5.454 150 5.698 160 5.249 2. Relevant equations y = A + Becx 3. The attempt at a solution https://www.physicsforums.com/threads/exponential-least-squares-method.845240/ https://commons.apache.org/proper/commons-math/userguide/leastsquares.html http://math.stackexchange.com/questions/1337601/fit-exponential-with-constant From the information provided in the three links above, to solve my problem I would need to solve the three partial derivatives using an appropriate initial guess. From my limited understanding, I could potentially use a number around 5.5 as an initial guess for c which would reduce the iterations required to find an optimal solution. However, I do not understand how to generate the 'model function' which is used by the least squares engine to evaluate the components. I have seen a few examples of generating the model function however I do not fully grasp how it is generated. A link below are additional examples. Hoping I can obtain assistance from you wonderful people. Thank you. http://www.programcreek.com/java-ap...ath3.fitting.leastsquares.LeastSquaresProblem PS - Sorry for the formatting, I could not find the relevant options to insert a table.