Hi all,

I was wondering if anybody knows of software to create a recurrence plot of data that is coded with a time point (in milliseconds), and a value from that time point. The software I have found so far assumes that the time series is uniformly sampled as far as I can tell. An example of my data is:

Time, Amplitude

11234, 9.6

11398, 10.2

12001, 1.7

12121, 2.0

I'd like to create a recurrence plot indicating the difference between the amplitude values, and also one where if a later occurring sample has a greater value than an earlier occurring sample that it is indicated as 1, and 0 otherwise.

Thanks,

Dan

## Non-uniform sampling of time series data

- sultornsanee
- Senior
**Posts:**29**Joined:**Tue Oct 12, 2010 21:05**Affiliation (Univ., Inst., Dept.):**Northeastern University**Location:**Boston, Massachusetts, USA**Research field:**Pattern Recognition Analysis**Location:**Network/Nano Science and Engineering Laboratory, Northeastern University, Boston, USA

### Re: Non-uniform sampling of time series data

You can download CRP toolbox (Dr. Norbert Marwan)

Sivarit Sultornsanee (Tony)

Network/Nano Science and Engineering Laboratory (NSE Lab)

360 Huntington Ave., Room 320 SN, Boston, MA 02038, USA

E-mail: SULTORNSANEE.S@HUSKY.NEU.EDU

Network/Nano Science and Engineering Laboratory (NSE Lab)

360 Huntington Ave., Room 320 SN, Boston, MA 02038, USA

E-mail: SULTORNSANEE.S@HUSKY.NEU.EDU

- Norbert
- Expert
**Posts:**183**Joined:**Wed Jan 4, 2006 11:03**Affiliation (Univ., Inst., Dept.):**Potsdam Institute for Climate Impact Research, Germany**Location:**Potsdam, Germany**Location:**Potsdam Institute for Climate Impact Research, Germany

### Re: Non-uniform sampling of time series data

Although the CRP toolbox allows to provide a certain vector with arbitrary time scale, finally, the plot of the matrix is equally sampled. Unfortunately.

But the solution is to use sparse matrices in Matlab and plot the RP using the

http://www.agnld.uni-potsdam.de/~marwan ... #long_data

However, I'm a bit concerned about this procedure. If we have larger distances, should then the recurrence point in the RP not be larger (covering a larger area in the plot)?

But the solution is to use sparse matrices in Matlab and plot the RP using the

*spy*command. This would allow non-equally sampled RPs. See here for an example how to use sparse/spy:http://www.agnld.uni-potsdam.de/~marwan ... #long_data

However, I'm a bit concerned about this procedure. If we have larger distances, should then the recurrence point in the RP not be larger (covering a larger area in the plot)?