i have a problem with my plot, i am not getting any values and the system gives me an empty plot.

a = 0;5; 
i0H2 = 10^(-7); 
i0Zn = 10^(-5); 
C = 7; 
R = 8;314; 
T = 298;15; 
F = 96485;

E0H2 = -0;83; 
E0Zn = -1;27; 
n = [-1,1]; 

EH2 = n + E0H2; 
EZn = n + E0Zn; 

iH2 = @(n)(i0H2 *( exp((a*F*n)/(R*T)) - exp((-a*F*n)/(R*T)))) ; 
iZn = @(n) (i0Zn * (exp((a*F*n)/(R*T)) - exp((-a*F*n)/(R*T)))); 

Log_iH2 = log10(iH2(n)); 
Log_iZn = log10(iZn(n)); 

plot(Log_iH2, EH2)
hold on 
plot(Log_iZn, EZn)
hold on 

[Matt J]

Look at what your data contains:

Log_iZn =

  -Inf  -Inf


EZn =

    -2     0

[Ammar Anayi]

how do i resolve the problem, what should i do with the code.

[Matt J]

Matlab is calculating what you asked it to. We cannot know what you really intended to calculate.

Answer 1

[John D'Errico]

Look at what you did.

a = 0;5; 

First, maybe you think this creates a vector in a? Instead, it just sets a to 0. Then it dumps 5 into the bit bucket.

i0H2 = 10^(-7); 
i0Zn = 10^(-5); 
C = 7; 
R = 8;314; 
T = 298;15; 
F = 96485;
E0H2 = -0;83; 
E0Zn = -1;27; 

Again, I wonder if you understand that just dumps the second number after the semi-colon into the bit bucket?

n = [-1,1]; 
EH2 = n + E0H2; 
EZn = n + E0Zn; 
iH2 = @(n)(i0H2 *( exp((a*F*n)/(R*T)) - exp((-a*F*n)/(R*T)))) ; 
iZn = @(n) (i0Zn * (exp((a*F*n)/(R*T)) - exp((-a*F*n)/(R*T)))); 
Log_iH2 = log10(iH2(n)) 

Log_iH2 = 1×2

-Inf -Inf

Log_iZn = log10(iZn(n))

Log_iZn = 1×2

-Inf -Inf

Finally, you try to plot those numbers. Since they are infinities, what do you expect to be plotted?

What you really wanted to do here is a complete guess. I won't even try to make one.