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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 ]
 dpb Posts: 9,850 Registered: 6/7/07
Re: Pairing two different values on one plot
Posted: Apr 15, 2013 2:33 PM

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...

--

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