MATLAB m-files for RDI ADCP data

Why not use RD Instruments' software?

RDI's software suite for processing and displaying ADCP data is terrific if you are doing work in real time or looking at profiles. For those of us using the ADCP for time series work, the time series display part of PLAYBACK is limiting. Most of us transfer the data to other software packages for plotting and viewing. What I offer here is a method of viewing the data in MATLAB.

What does RDI2CDF do?

The m-file rdi2cdf.m is a stand alone function which converts the RDI ADCP broadband or workhorse data format to netCDF. I will not go into the advantages of netCDF here, see for yourself at UNIDATA.

I have included a listing of a typical ADCP netCDF file header which shows the detail of how ADCP data is stored in netCDF.

What does ADCPMENU do?

The image below shows the menu that is displayed when adcpmenu.m is run from the MATLAB command window. Clicking on the menu buttons allows the user to load netCDF data, do beam to earth conversions, plot data in 2D or 3D and obtain basic statistics. Data are loaded into the main MATLAB workspace and can be further manipulated and displayed beyond the basic plotting routines executed by adcpmenu.m.

A typical work session may involve plotting all the data (which causes it to be loaded into the workspace), taking a quick look at the data, saving the main workspace to matlab.mat, then doing my own thing with the data from the command line prompt. If I change things irretrievably, or so that the variables are no longer compatible with adcpmenu, I can simply reload the workspace and get back to where I started.

The following are example plots to give you some idea of how data is displayed by adcpmenu.

• Plots of variable leader data (temperature and orientation)
• Two dimensional plot of velocity. The controls at the top of the plot allow the user to display any bin or any beam by ensemble in the axes without rendering a new plot window.
• Three dimensional color plot of intensity

Prerequisites:

• REQUIRED: MATLAB 4.0, found at the Mathworks
• REQUIRED: MEXCDF binary for your platform. MEXCDF is a MATLAB mex file.
• RECOMMENDED: netCDF (network Common Data Form)

Gory details:

• View the readme file right now.
• View the most significant m-files from here.
• Read the FAQ.

Caveats:

• Although I know some UNIX, I use PC's almost exclusively. These m-files have been written for MATLAB for windows and I have no means (nor time!) to test them on a UNIX box. The only known problems so far has been byte order inconsistencies involved with my example raw data file. I suggest that UNIX users should supply their own ADCP data or try downloading the unzipped version of the example data file directly here.
• These files are focused for our applications here at the Woods Hole Center. As I receive feed back (and find the time) I will add more features, streamline code, improve documentation, etc., but please bear with me, the maintenance of this code is not my primary job function here at USGS.

Download the ZIP archive which contains all the m-files and example data. In Netscape, click the right mouse button on the link and choose 'save link as...'

Click here to download the WinZIP program.

Contributions from others:

Rodolphe Rousselet (rous@shom.fr) of EPSHOM - France has contributed a patch that should eliminate fread problems on Sun workstations, download my_fread.m, a new version of fread.m.

Upgrade to MATLAB 5.0 in work!

ENJOY!