I carried out a physics experiment and I wanted to analysis the problem with matlab. I have some code in matlab that "works" as in it gives ok result but the numbers used are quite nonsensical, I need help making the reworking the equation with real numbers. I am not sure if this is the correct thread, if not sorry. Here is my code:(adsbygoogle = window.adsbygoogle || []).push({});

My main problem is using very large numbers like "5500000". What I would like to do, is make the exp(a*exp(b*r^2)) component be the part of the function that determines the number of rings, where a=2Npi and N would determine the number of rings. However I am not sure how to go about normalizing the rest of the constants so that this would be the case.Code (Matlab M):

format long;

clear all;

I0=39546.95973;

i=sqrt(-1);

r=0.0;

fid=fopen('plot.txt','w') %Êý¾ÝÐ´ÔÚplot.txt

for m=1:300

p(m)=m*0.0001-0.015; %¿ÉÒÔµ÷Õû×÷Í¼²½³¤

In(m)=0;

dddr=0.00001;

for r=0.0:dddr:0.010 %¸ù¾ÝÊÕÁ²ÐÔµ÷Õû»ý·ÖÉÏÏÞºÍ²½³¤

In(m)=In(m)+r*besselj(0,5500000*r*p(m))*exp(-4.325259515570934*10^6*r*r)*exp(-i*(5500000*r*r-27.014528191562999*exp(-4.325259515570934*10^6*r*r)));

end

I(m)=3.025*10^13*dddr^2*I0*(norm(In(m)))^2;

fprintf(fid,'%9.4f %9.4f \n',p(m),I(m));

end

fclose(fid)

fclose all;

hold off

plot(p,I); %»Í¼

hold on

return;

Mod note: I added code tags. Please do that every time you post code.

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# Need help with integral

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