Quasi-Newton least squares -- exponential fit

Here the residual is : F(x;ti) = a0 + a1*exp(b1*ti) + .... + an*exp(bn*ti) - yi

Please choose the number of exponential terms
n = Important: n <= 4 !

Specify the original coefficients, 2*n+1 numbers, in this textfield.
The coefficients must be given in the order x = a0,a1,b1, ... , an,bn.
In the output these are x[1],x[2],x[2+n1],x[3],..,x[1+2 n1]!
x=

Specify the interval for the variable t:
a= b=

Specify the number m of data points:
m= Important: 2n+1 <= m <= 200 !

Please specify the errorlevel here:
level= Important: 0 <= level <= 1

use the standard parameters given below
My own settings:
xtol = terminate if solution x changes less than this (rel)
ftol = terminate if sum of squares changes less than this (rel)
maxstep = max number of steps allowed
maxfev = max number of function evaluations allowed
iprint = -1 = none , 0 = final , 1 = final and short iteration protocol
index1 = index for a component of x to be printed over stepnumber
index2 = index for a second component of x to be printed over stepnumber

Click on "evaluate", in order to submit your input.

Back to the theory page

 Back to the top!

13.12.2013