How to plot datetime array?

I would like to plot a vector, r, as a function of time. The two vectors I have are:

r'

   1.0e+03 *

    0.0179
    0.0180
    0.0184
    0.0184
    0.0189
    0.0189
    0.0189
    0.0189
    0.0190
    0.0190

ds = 
10×1 datetime array

   02-Feb-2018 11:08:11
   02-Feb-2018 12:08:13
   02-Feb-2018 01:08:14
   02-Feb-2018 02:08:15
   02-Feb-2018 03:08:17
   02-Feb-2018 04:08:18
   02-Feb-2018 05:08:20
   02-Feb-2018 06:08:21
   02-Feb-2018 07:08:23
   02-Feb-2018 08:08:24

However, when I try to plot them:

plot(datenum(ds), r, '-o')
datetick('x', 'dd-mmm-yyyy HH:MM:SS')

I get this graph (see attached). I would like for each point to have a corresponding time and date on the x-axis, if it is possible.

Answer 1

[Walter Roberson]

plot(ds, rs, '-o')

From R2016b onward, you can use datetime objects as the x or y axes. (Exact release varies a bit with variety of graph being plotted.)

[Asher Zaidi]

I get the following error:

 >> plot(ds,r, '-o')
Data inputs must match the axis configuration. A numeric axis must have numeric data inputs or
data inputs which can be converted to double.

[Walter Roberson]

You could get that if you were trying to do a datetime plot on top of an existing numeric axes.

If you are trying to draw on top of an existing axes, then you might have "hold on" in effect, and that might have affected the xtick values that the axes thought should be used.

When I use your commands together with

   ds = datetime({'02-Feb-2018 11:08:11'
   '02-Feb-2018 12:08:13'
   '02-Feb-2018 01:08:14'
   '02-Feb-2018 02:08:15'
   '02-Feb-2018 03:08:17'
   '02-Feb-2018 04:08:18'
   '02-Feb-2018 05:08:20'
   '02-Feb-2018 06:08:21'
   '02-Feb-2018 07:08:23'
   '02-Feb-2018 08:08:24'});
  r = 1e3 * [   0.0179
    0.0180
    0.0184
    0.0184
    0.0189
    0.0189
    0.0189
    0.0189
    0.0190
    0.0190];

then xtick creates labels for every 3 hours.

[Asher Zaidi]

I see, thank you!

Answer 2

[Aron Magesh]

If you have used hold on function, make sure to use the hold off as well to avoid this error.

[Bucks Lin]

wow!

thanks Aron!! your tips save my day.