# Unable to plot a wavefunction

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Sergio Manzetti on 3 Jan 2018
Commented: Sergio Manzetti on 4 Jan 2018
Hi, I wonder if any of you can try to plot this and see if they also get a weird bar?
syms h g x C t m e p c
h = 1.0545718E-34
g = 5.344285879E-28
E = 1
Z = - (exp(-(x*(g*1i + (- 2*g^2 + E)^(1/2)))/h)*(g*1i - (- 2*g^2 + E)^(1/2)))/(2*(E - 2*g^2)^(1/2)) + (exp(-(x*(g*1i - (- 2*g^2 + E)^(1/2)))/h)*(g*1i + (- 2*g^2 + E)^(1/2)))/(2*(E - 2*g^2)^(1/2))
fplot(real(Z), [ -4, 4 ])
figure(1)
Thanks!
If so, why?

David Goodmanson on 4 Jan 2018
Hi Sergio,
This function appears to have scaling issues. If you plot
figure(1)
fplot(real(Z), [-2*h, 2*h])
figure(21)
fplot(imag(Z), [-2*h, 2*h])
you can see the function. I believe this addresses the question, but there are other things going on too. Possibly you were using E=1 just for test purposes, but compared to that value, 2*g^2 is infinitesimal. Also the function itself is an increasing exponential which is not good for a wave function unless there is some kind of hard boundary.
Sergio Manzetti on 4 Jan 2018
Thanks David, this is excellent! Indeed E=1 was set to test. I will try this out as you suggest! Best wishes