plotting Timeseries, setting xlim only to the range of data

while ploting a timeseries Matlab automatically takes xlim values beyond the actual data time limit. For example I have time start date and end as

beginTime='12-OCT-2012 14:00:00'; 
finishTime='12-OCT-2012 18:00:00'

but when I plot I get plot with xlim from '12-OCT-2012 13:55:12' to '12-OCT-2012 18:43:12'. How can I fix the xlim to exactly the time range of my data ?

Answer 1

[per isakson]

Warning: Not tested

date_frmt = 'dd-mmm-yyyy HH:MM:SS';
set(axes_handle,'XLim',[datenum(beginTime,date_frmt),datenum(finishTime,date_frmt)])

[Meh]

Thanks Per, but I am getting strange dates on my plot. XLim is now from 18-Mar-4025 14:00:00 to 18-Mar-4025 18:00:00. Any suggestion? I used gca instead of axes_handle, but I don't think it plays any role, does it?

[per isakson]

I didn't pay enough attention to the difference between "timeseries" and "time series". The former is a Matlab class and the latter is a signal that depends on time. I've never used "timeseries" seriously.

With "time series", i.e. the old way, there is no problems:

    date_frmt = 'dd-mmm-yyyy HH:MM:SS';
    beginTime='12-OCT-2012 14:00:00'; 
    finishTime='12-OCT-2012 18:00:00';
    t = [ datenum(beginTime,date_frmt) : 1/(24*60) : ... 
          datenum(finishTime,date_frmt) ];
    y = randn( size(t) );
    plot( t, y )
    axes_handle = gca;
    datetick
    set(axes_handle,'XLim', ... 
         [datenum(beginTime,date_frmt),datenum(finishTime,date_frmt)])

.

The class "timeseries" is a bit too smart to my taste.

• Firstly, I cannot recreate the time axis you describe.
• Secondly, I'm not sure whether datetick and/or set(h,'XLim'...) should be used - most likely not.

I tried

    ts = timeseries( y, t );
    ts.TimeInfo.Format = date_frmt;
    ts.Time = ts.Time - ts.Time(1);  % ????
    figure
    plot( ts )

Obviously, serial date numbers are not the default with timeseries.

    >> ts.TimeInfo
      tsdata.timemetadata
      Package: tsdata

      Non-Uniform Time:
        Length       241

      Time Range:
        Start        0 seconds
        End          1.666667e-01 seconds

      Common Properties:
              Units: 'seconds'
             Format: 'dd-mmm-yyyy HH:MM:SS'
          StartDate: ''

Most likely, the problems you see depend one the values of the properties, Start, Unit and/or StartDate.

"18-Mar-4025 14:00:00" is approx. two times 2013. Probably, a start value is "added" auto-magically to the XLim values of set(axes_handle,'XLim', ....

/over