# Error using plot, vectors must be same length

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Saad Khan on 9 Dec 2019
Dear MATLAB experts,
sorry for the dumb question but im in serious need of help.
Im doing alot of different calculations and some of the results that i will be using is placed in two vectors, c and H.
the size for them is: c: 64x4double and H:69x1double.
Im trying to do a plot of H and c where H is the x-axis and c being y-axis.
I have tried changing the code but it messes up my calculations.
If anyone knows a solution to avoid this it would be much appreciated.
I attached the code in the file: optim_o2_co_vs_height.m
p.s im still learning how to use MATLAB
Best Regards

Saad Khan on 9 Dec 2019
Hi,
that's what im looking for, some way to force it to plot identical size of the "c".
Is it possible to crop H?
its a concentration vs height plot and a concentration vs temperature that im trying to do.
Best Regards
Nicolas B. on 9 Dec 2019
To crop H, you need to decide which samples of H are not relevant to plot data. E.g:
H(5:end)
or
H(1:end-5)

Nicolas B. on 9 Dec 2019
Edited: Nicolas B. on 9 Dec 2019
I have a question of logic about what you want to plot. Because you want t plot with:
• x-axis: H, size 69x1
• y-axis: c(:, 1), size 64x1
So there are 5 missing samples in the y-axis!
You should define whether you want to crop your H-vector while plotting or if you need to add some values to c in order to plot.
Edit: you will have the same problem at line 166 where Temperature's size is also 69x1.

Saad Khan on 9 Dec 2019
I just tried to change the ODE solver and I get different sizes of the different vectors. I assume its because of the limits each ODE has.
For the H, i just want values until 3 is reached or 3+ 0.09.
Should i just implement it in the plot commando e.g:
plot(H(1:end-5),c(1:etc....)?
Best Regards

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