curve fitting for the optimal value of a constant

1 view (last 30 days)
Hey here, I am trying to find the value of k(unknown constant) and for that I have collected data points from a curve and then fit into other(as attached). I had found the result i.e., 0.1300 but it isn't matching with the result which is 1.
So, can anybody tell me if there is any mistake.
Thankyou
r=0:1*10^-9:50*10^-9;
l=50*10^-9;
e=1.6*10^-19;
V=((1.44).*exp(3.257*((r./l).^2)).*besselk(0,(3.257*((r./l).^2))))./(e.^2);
R=r/l;
plot(R,V)
h=findobj(gca, 'Type', 'line');
R=h.XData
V=h.YData
k0 = rand()*10;
R=[0.0200,0.0400,0.0600,0.0800,0.1000,0.1200,0.1400,0.1600,0.1800,0.2000,0.2200,0.2400,0.2600,0.2800,0.3000,0.3200,0.3400,0.3600,0.3800,0.4000,0.4200,0.4400,0.4600,0.4800,0.5000,0.5200,0.5400,0.5600,0.5800,0.6000,0.6200,0.6400,0.6600,0.6800,0.7000,0.7200,0.7400,0.7600,0.7800,0.8000,0.8200,0.8400,0.8600,0.8800,0.9000,0.9200,0.9400,0.9600,0.9800,1.0000];
V=1.0e+38*[3.8070,3.0381,2.5965,2.2900,2.0580,1.8734,1.7216,1.5937,1.4841,1.3888,1.3051,1.2309,1.1646,1.1050,1.0510,1.0020,0.9572,0.9161,0.8783,0.8433,0.8110,0.7810,0.7530,0.7269,0.7025,0.6796,0.6581,0.6379,0.6189,0.6009,0.5839,0.5678,0.5525,0.5380,0.5243,0.5111,0.4987,0.4868,0.4754,0.4645,0.4541,0.4442,0.4346,0.4255,0.4167,0.4083,0.4002,0.3924,0.3849,0.3777];
bestk = lsqcurvefit( @(k,R)(1./((sqrt((k.^2)+(R.^2))).*(e.^2))), k0, R, V)

Answers (0)

Categories

Find more on Interpolation in Help Center and File Exchange

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!