# how do I modify the axis in plot(x,y)?

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claudio on 7 Mar 2011
Answered: laurent jalabert on 23 May 2019
Hi, I need to plot the following vectors: x=[0.05 0.1 0.3 0.5 1 5 10 20 30 40 50] y=[0.8 0.83 0.9 0.93 0.93 0.9 0.9 0.94 0.95 0.95 0.95] plot(x,y)
My problem is that the vector x don't appears explicitly in the axis and also the scale of the axis is not constant. I need something like:
----------------------------------------------------
0.05 0.1 0.3 0.5 1 5 10 200 ...
your help will be very useful for me

Matt Tearle on 7 Mar 2011
So you want the x-axis to be nonlinear (but not necessarily log)? Well, you can always cheat. Do what Matt Fig suggests, but change the plot command to just plot(y) and the next line to
set(gca,'XTick',1:length(x))
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Matt Tearle on 8 Mar 2011
I'm not sure I understand what you're after. If you want to leave a bit of space above and below the data, just use axis or ylim and pad it out a bit: ylim([ymin-dy ymax+dy]) (where dy is some small "padding" value)

Matt Fig on 7 Mar 2011
Is this more to your liking?
x=[0.05 0.1 0.3 0.5 1 5 10 20 30 40 50];
y=[0.8 0.83 0.9 0.93 0.93 0.9 0.9 0.94 0.95 0.95 0.95];
plot(x,y)
set(gca,'xtick',x);
set(gca,'xticklabel',num2str(x.'));
Now, separately try this and see if it is what you need. When you have such large differences in scale, there can be problems representing all the data points on an axis.
set(gca,'xscale','log') % Set to linear to go back.
claudio on 7 Mar 2011
Ok Matt Thanks,
Now, I just need to represent all the data points on x axis uniformly, but I can't find the way. Could you help me pls?

laurent jalabert on 23 May 2019
hello, what about a function to modify the xTicks label with a non-linear function of x ?
For example, displaying the grid as x^3 ?