Dear Easwar
I have tried to use a new method to solve my problem after getting your new suggestion. As you know, these are my original data listed below:
X(x) B(Y)
0 0.45968
0.03067 0.45575
0.05205 0.45254
0.1 0.44414
0.17067 0.42936
0.34311 0.38642
0.58933 0.32282
1 0.24072
1.50133 0.18831
2.176 0.15892
2.62578 0.14516
3.26133 0.12791
3.89067 0.11652
4.42933 0.11048
5.13867 0.10211
5.992 0.09002
7.016 0.08361
7.784 0.07652
8.86133 0.06993
10 0.0638
I tried to get the expression of function y=f(x) for these data in order to get ratio=f(x/3)/f(x). Although we fit our data (in col B) by using
y=p1+p2*x+p3*x^2+p4*x^3+p5*x^4+p6*x^5+p7*x^6+p8*x^7+p9*x^8+p10*x^9+p11*x^10 ...(1),
a series of parameters p1 to p11 is not good enough. So according to the equation (1), I cannot get a reasonable Ration=f(x/3)/f(x).
You suggestion is very good. I tried to use
y=f(x)=nlsf.p1+nlsf.p2*col(x)+nlsf.p3*col(x)^2+nlsf.p4*col(x)^3+nlsf.p5*col(x)^4+nlsf.p6*col(x)^5+nlsf.p7*col(x)^6+nlsf.p8*col(x)^7+nlsf.p9*col(x)^8+nlsf.p10*col(x)^9+nlsf.p11*col(x)^10 ...(2)
It is very close to my original data. Although I do not know what p1 to p11 are, I can get f(x/3). In order to get f(x/3), I change X(x) data by dividing 3. Then set the column as a new X(x). I still use equation (2) to calculate and get a new column which is f(x/3).
Finally, I reach my purpose to get f(x/3)/f(x).
Thank you again.
Yang
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The problem has been solved
Posted - 01/25/2005 : 4:33:57 PM
