Why this for loop showing this error?

clc;close all;clear all
syms r ph phi    
lam=532 *10^-9;
k=2*pi/lam;
omega=30;
w0=0.002;
rho=1;p=1;
z=100;
R=0.06;
m1=1

m1 = 1

N=3;
 
for l1=-N:1:N
    l1
%to calculate E0
    for s1=0:m1
        E = 1./(w0^2) + (1i*k)./(2*z);
        Con1 = (1i./(2.*lam.*z)).^2 .*exp(-1i.*k.*r.*r./z) .* ((1./(2.*1i.*sqrt(E))).^(2*m1));
        E1 =  exp((((omega/2)-(r.*cos(ph))).^2)./E).* exp((((omega/2)-(r.*sin(ph))).^2)./E).*hermiteH(s1,1i*(omega./2 - r*cos(ph))./sqrt(E)).*hermiteH(m1-s1,1i*(omega./2 - r*sin(ph))./sqrt(E)) - exp((((-omega/2)-(r.*cos(ph))).^2)./E).* exp((((-omega/2)-(r.*sin(ph))).^2)./E).*hermiteH(s1,-1i*(-omega./2 + r*cos(ph))./sqrt(E)).*hermiteH(m1-s1,-1i*(-omega./2 + r*sin(ph))./sqrt(E));
        I1 = Con1.*((1i*p).^(m1-s1)).*nchoosek(m1,s1).*E1;
    end
    % to calculate E0*
    
    for s2=0:l1
        EE = 1./(w0^2) - (1i*k)./(2*z);
        Con2 = (-1i./(2.*lam.*z)).^2 .*exp( 1i.*k.*r.*r./z) .* ((-1./(2.*1i.*sqrt(EE))).^(2*l1));
        E2 =  exp((((omega/2)-(r.*cos(phi))).^2)./EE).* exp((((omega/2)-(r.*sin(phi))).^2)./EE).*hermiteH(s2,1i*(omega./2 - r*cos(phi))./sqrt(EE)).*hermiteH(l1-s2,1i*(omega./2 - r*sin(phi))./sqrt(EE)) - exp((((-omega/2)-(r.*cos(phi))).^2)./EE).* exp((((-omega/2)-(r.*sin(phi))).^2)./EE).*hermiteH(s2,-1i*(-omega./2 + r*cos(phi))./sqrt(EE)).*hermiteH(l1-s2,-1i*(-omega./2 + r*sin(phi))./sqrt(EE));
        I2 = Con2.*((1i*p).^(l1-s2)).*nchoosek(l1,s2).*E2;
    end
    
    %to calculate CSD
    I = I1.*I2;
    IQ = I.*exp(1i.*(l1-m1).*(ph-phi)).*exp((-2^(5/6)).*((1 - cos(ph-phi)).^(5/6)).*(r.^(5/3)))./(rho.^(5/3)).*r;
    fun = matlabFunction(IQ,'Vars',[ph,phi,r]);
    result_1 = abs(integral3(@(ph,phi,r)fun(ph,phi,r),0,2*pi,0,2*pi,0,R)) 
end

l1 = -3

Unrecognized function or variable 'I2'.

Answer 1

[Vilém Frynta]

I have tried your code and it seems like your for loop isn't triggered at all. Which means, none of the calculations happen and none of the variables exist.

This for loop:

for s2=0:l1
        EE = 1./(w0^2) - (1i*k)./(2*z);
        Con2 = (-1i./(2.*lam.*z)).^2 .*exp( 1i.*k.*r.*r./z) .* ((-1./(2.*1i.*sqrt(EE))).^(2*l1));
        E2 =  exp((((omega/2)-(r.*cos(phi))).^2)./EE).* exp((((omega/2)-(r.*sin(phi))).^2)./EE).*hermiteH(s2,1i*(omega./2 - r*cos(phi))./sqrt(EE)).*hermiteH(l1-s2,1i*(omega./2 - r*sin(phi))./sqrt(EE)) - exp((((-omega/2)-(r.*cos(phi))).^2)./EE).* exp((((-omega/2)-(r.*sin(phi))).^2)./EE).*hermiteH(s2,-1i*(-omega./2 + r*cos(phi))./sqrt(EE)).*hermiteH(l1-s2,-1i*(-omega./2 + r*sin(phi))./sqrt(EE));
        I2 = Con2.*((1i*p).^(l1-s2)).*nchoosek(l1,s2).*E2;
end

Variables EE, E2, I2 do not exist after this for loop. For loop doesn't run.

[Walter Roberson]

for l1=-N:1:N

so l1 is going to start negative. Then 0:l1 is going to be empty, so as @Vilém Frynta indicates, the for s2 loop body is not going to be executed -- at least not until l1 reaches 0.