I need help fixing my MATLAB code, I got a $1/2.$ Here are the instructions:

General curve fitting with nlinfit

Assume these variables are already defined:

$x\_$list $-$ list of $x$ values

Y$\_$list $-$ list of y values

$x-$ single $x$ value

Write a MATLAB code segment that uses nlinfit to determine the best fit curve for the points in X$\_$list and Y$\_$list according to this equation

$y=\frac{1}{A}+\frac{B}{x}+e^{Cx}$

where $A,B,$ and $C$ are constants. Use initial guesses of $A=1,B=2,$ and $C=0.$

Your results should be stored in a structure named fitData with the following fields:

A : determined coefficient A

: determined coeeficient $B$

: determined coefficient $C$

$x$ : provided value of $x$

$Y$ : value of your curve fit equation evaluated at $x$

Example Test Case:

clear all; clc; format compact; format short g;

X$\_$list $=[1,3,5,7,9]$;

Y$\_$list $=[4\mathrm{.}1054,3\mathrm{.}7485,5\mathrm{.}4772,9\mathrm{.}036,15\mathrm{.}68]$;

$x=12$;

$\%$ your code for the submit to MATLAB box here

$\%6\%\%\%\%$

fitData

Should display this result in the command window

fitData $=$

$X$: $12$

$Y$: $37\mathrm{.}338$

$A$: $1\mathrm{.}8003$

$B$: $2\mathrm{.}2001$

$C$: $0\mathrm{.}3$

Your code should work for any set of starting values. Do not include test cases, clear all, etc as part of your submission.

My Code:

clear all; clc; format compact; format short g;

X$\_$list $=[1,3,5,7,9]$;

Y$\_$list $=[4\mathrm{.}1054,3\mathrm{.}7485,5\mathrm{.}4772,9\mathrm{.}036,15\mathrm{.}68]$;

X $=12$;

fitData $=$ struct$()$;

y $=$ @$($b$,$x$)1./$b$(1)+$ b$(2)./$max$($x$,$ eps$)+$ exp$($b$(3).*$x$)$;

Initial$\_$Coff $=[1,2,0]$; $\%$ A $=1,$ B $=2,$ C $=0$

New$\_$Coff $=$ nlinfit$($X$\_$list, Y$\_$list, y$,$ Initial$\_$Coff$)$;

Y$\_$new $=$ y$($New$\_$Coff, X$)$;

fitData.X $=$ X;

fitData.Y $=$ Y$\_$new;

fitData.A $=$ New$\_$Coff$(1)$;

fitData.B $=$ New$\_$Coff$(2)$;

fitData.C $=$ New$\_$Coff$(3)$;

fitData

Result:

MATLAB results:

Start of test case $1$

C $=$

$1\mathrm{.}800349252553742\mathrm{.}200102119579330\mathrm{.}300002531051947$

fitData $=$

struct with fields:

X: $12$

Y: $37\mathrm{.}338$

A: $1\mathrm{.}8003$

B: $2\mathrm{.}2001$

C: $0\mathrm{.}3$

checking answer

$++++++++$GOOD$++++++++$

End of test case $1$

Start of test case $2$

C $=$

$6\mathrm{.}09975\mathrm{.}30\mathrm{.}1991$

fitData $=$

struct with fields:

X: $12$

Y: $37\mathrm{.}338$

A: $1\mathrm{.}8003$

B: $2\mathrm{.}2001$

C: $0\mathrm{.}3$

checking answer

Output $1$ does not match

End of test case $2$

$1$ of $2$ test cases corrects