MATLAB: Please, how to plot for this code

plot

k = -2:0.1:2;
g = ((2*cos(2*k))-2)/(1i*k);
plot(k,g)

Best Answer

Read about element by element operations.

k = -2:0.1:2;
g = ((2*cos(2*k))-2)./(1i*k);   % use ./
plot(k,abs(g))
hold on
plot(k,real(g))
plot(k,imag(g))
legend('abs','real','imaginary')

Related Solutions

MATLAB: Surf cannot be complex

You forgot a couple of dots (g^ -> g.^) in your code.

d1 = 0.0002:0.00001:0.0004;
g1 = 70:90;
[d,g] = meshgrid(d1,g1);
t = 6;
k = 0.7;
m = 0;
I = (48*d.*t.^2*k.*(k-1).*(k-2).*g.^((k-3)/k)-12*d.*k.*(k-1).*...
    g.^((k-2)/k)-16*d.*t.^4*k.*(k-1).*(k-2).*(k-3).*g.^((k-4)/k))+...
    3*(2*d.*k.*g.^((k-1)/k)-4*d.*t.^2*k.*(k-1).*g.^((k-2)/k)).^2+...
    4*(8*d.*t.^3*k.*(k-1).*(k-2).*g.^((k-3)/k)-12*d.*t.*k.*(k-1).*...
    g.^((k-2)/k)).*(2.*t.*d.*k.*g.^((k-1)/k)+m)+6.*(2*d.*k.*...
    g.^((k-1)/k)-4*d.*t.^2.*k.*(k-1).*g.^((k-2)/k)).*(2*t.*d.*k.*...
    g.^((k-1)/k)+m).^2+(2*t.*d.*k.*g.^((k-1)/k)+m)^4;
h = 2*d.*k.*(g.^(1/k)-2*t.^2*(k-1)).*g.^((k-2)/k);
Z = I./(h.^2);
surf(d,g,Z)

MATLAB: Help please, problem with integration

I'm not terribly sure why you tell us that A=1, as it is the only parameter that is not used at all here. I'm also not at all sure why you have C1=eval(C1) in there, as we never see C1 either. And your title claims that this somehow includes the gamma function. Don't see that either.

You have unknown parameters X and Y. How could you expect to do a numerical integration with them as unknowns? Or are X and Y known, and you are not telling us what they are? Can we guess? If so, then I pick:

X = 42;
Y = 17;

If X and Y are known parameters, then I don't see the problem with a numerical integration, since an analytical solution is clearly not to be found. Not every problem has a clean solution. I'd start with quadgk or integral.

Best Answer

Related Solutions

MATLAB: Surf cannot be complex

MATLAB: Help please, problem with integration

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