How do I get MATLAB to automatically account for missing XTick labels?

I've run into a scenario where MATLAB won't include the final xtick in some plots. For example, if I use the following code;

Time = [5 10 15 20 22.23];
Alt = [3 9 16 21 23];
plot(Time, Alt);
title('Altitude Vs Time');
set(gca, 'XLim', [0 max(Time)]);
xlabel('TALO (Sec)');
ylabel('Alt (Miles)');

I get a plot of altitudes vs time, where the desired x-axis tick values begin with 0, end with 20, at 5 second intervals. What I actually need is the same plot with X-axis ticks of 0, 5, 10, 15, 20, and 25.

Is there a way to get get MATLAB to automatically make the a-axis ticks extend past 20 to 25?

Answer 1

[Star Strider]

Make one small change in the ‘set’ command in your original code, and the upper 'XLim' takes care of itself:

set(gca, 'XLim', [0 5*ceil(max(Time)/5)]);

This will automatically round the upper 'XLim' value to the next multiple of 5. Change the 5 values to something else if you want it to round to another value. Experiment with it.

[Brad]

Star Strider, I've tested this on several data sets and it appears to work flawlessly. But I have to ask, why 5*ceil(max(Time)/5? Wouldn't ceil(max(Time)) produce consistently similar results?

[Star Strider]

The 5 tells it specifically to round to the next highest multiple of 5. I got the impression that was what you wanted. (Changing the 5 to 10 would round it to the next highest multiple of 10, etc.)

When I tested it, ceil(max(Time)) rounds to the next highest integer. If that’s what you want, then go for it! It will consistently produce similar results.

The integer value you choose for the constants (the default being 1 if you don’t specify a value) depends on what you want it to round up to. You can of course replace the integers by variables and then declare the variable as a specific value for each plot or all plots.

[Brad]

Interesting.

I tested this approach on several data sets, some of which had multiples much larger than 5. I held the value of 5 constant, and it still ran like a champ, regardless of the data set. More testing is in order, but I'm a fan. Thanks for taking a look.

[Star Strider]

My pleasure!