| T O P I C R E V I E W |
| blochos |
Posted - 06/18/2009 : 12:05:51 PM
Origin Ver. and Service Release (Select Help-->About Origin): 8SR4, v8.0951 (B951)
Operating System:XP Professional
Hi!
I have a problem with fitting many curves simultaneously (with some shared parameters). I want to fit e.g 14 curves. 7 of them with the following functions (I write functionS because there will be in fact 7 functions which differ in some constants)
y1=J0+Jm1*(1-exp(-(x-t0)/l1))+Jm2*(1-exp(-(x-t0)/l2))+Jm3*(1-exp(-(x-t0)/l3))+(x-t0)/e0
y2=..
.
.
.
y7=...
And the other 7 curves with this formula (as well 7 functions differing in constants):
y1=Jmax-J0-(Jm1*(1-exp(-(x-t0)/l1))+Jm2*(1-exp(-(x-t0)/l2))+Jm3*(1-exp(-(x-t0)/l3)))
y2=..
.
.
.
y7=...
All the 14 curves must be fitted at the same time
How to do this in Origin? Please help 
|
| 4 L A T E S T R E P L I E S (Newest First) |
| tony_lincoln |
Posted - 08/14/2009 : 5:38:51 PM
Add all plots in active page--- This is the key point for the visualization of several curves in the same graph.
Thanks.
TOny |
| tony_lincoln |
Posted - 08/14/2009 : 5:09:43 PM
Suppose that I have 7 curves. I want to fit these 7 curves simultaneously using the same equation (of course, different parameters). After fitting, I want to visulize these 7 curves in the same graph. Is this visualization possible? If so, how?
Thanks.
Tony |
| Ibex |
Posted - 06/29/2009 : 10:03:15 AM
Maybe you could add something like
if (class==1) y=J0+Jm1*(1-exp(-(x-t0)/l1))+Jm2*(1-exp(-(x-t0)/l2))+Jm3*(1-exp(-(x-t0)/l3))+(x-t0)/e0;
if (class==2) y=Jmax-J0-(Jm1*(1-exp(-(x-t0)/l1))+Jm2*(1-exp(-(x-t0)/l2))+Jm3*(1-exp(-(x-t0)/l3)));
and set class fixed to 1 or 2 for the first 7 or second 7 curves. The different constants for the different curves you could also set as fixed (but not shared) variables.
Ibex |
| easwar |
Posted - 06/19/2009 : 09:42:17 AM
Hi,
This is currently not supported in Origin, you can perform global fit with parameter sharing between different datasets, with only one function, not different function for each dataset.
We will consider this for a future version, thank you for the inquiry.
Easwar
OriginLab |
