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Topic: Pairing two different values on one plot
Replies: 19   Last Post: Apr 18, 2013 2:44 AM

 Messages: [ Previous | Next ]
 Derek Goring Posts: 3,922 Registered: 12/7/04
Re: Pairing two different values on one plot
Posted: Apr 16, 2013 12:41 AM

On Tuesday, April 16, 2013 3:12:05 PM UTC+12, PK wrote:
> dpb <none@non.net> wrote in message <kkhh4h\$h36\$1@speranza.aioe.org>...
>

> > On 4/15/2013 1:44 AM, PK wrote:
>
> > > "Nasser M. Abbasi" wrote in message <kkg6na\$kc5\$1@speranza.aioe.org>...
>
> > >> On 4/15/2013 1:09 AM, PK wrote:
>
> > ...
>
> >
>
> > >> > Timestamp=
>
> > >> > 201203291200000
>
> > >> > 201203291215000
>
> > >> > 201203291230000
>
> > ...
>
> > >> > 201203291400000
>
> > >> > 201203291415000
>
> > >> >
>
> > ...
>
> >
>
> > >> > Now I want to plot Timestamp on x-axis and Data on y-axis so that I
>
> > >> can find
>
> > >> >the value of data at particular time.
>
> > >> >
>
> > >> > I have used
>
> > >> > plot (Data, Timestamp);
>
> > >> > but the output is awefuly different than ploting Data itself.
>
> > ...
>
> >
>
> > >> Should not this be:
>
> > >>
>
> > >> plot (Timestamp, Data );
>
> > >>
>
> > >> normally one puts time on the x-axis, as things normally are function
>
> > >> of time? When you do plot(Data), then Matlab puts i=1:N on the
>
> > >> axis by default, where N is length of Data.
>
> > ...
>
> >
>
> > > as plot(A,B); plots A on y-axis and B on x-axis, plot (Timestamp, Data )
>
> > > does not fix the issue. only swaps the axis.
>
> >
>
> > To see at least part of the problem and why you need datenums if want
>
> > other than ordinal x axis values, try
>
> >
>
> > diff(Timestamp(1:10)/10E2)
>
> >
>
> > at the command line and observe what you get...
>
> >
>
> > --
>
> thanks for ur replies.
>
>
>
> However,use of
>
> dn=datenum(ts(:,1:12),'YYYYmmddHHMM');
>
> gives an error
>
> " ??? DATENUM failed.
>
> Failed on converting date string to date number."
>
>
>
> I thinks the format 'YYYYmmddHHMM' is not valid.
>
>
>
> if my timestamp were 2012-03-29-15-00, I could have used "YYYY-mm-dd-HH-MM".but its not the case.
>
>
>
> again my time stamp are sorted and plot(x,y,'*') would not work either.
>

Date Subject Author
4/15/13 PK
4/15/13 Nasser Abbasi
4/15/13 PK
4/15/13 Nasser Abbasi
4/15/13 Lothar Schmidt
4/15/13 dpb
4/15/13 PK
4/16/13 Derek Goring
4/16/13 PK
4/16/13 PK
4/16/13 dpb
4/16/13 Steven Lord
4/16/13 dpb
4/16/13 PK
4/16/13 dpb
4/17/13 PK
4/17/13 dpb
4/18/13 PK
4/15/13 dpb
4/15/13 dpb