Ferret - Data Visualization and Analysis
your ferret in large and complex gridded data sets.
Documentation
Ferret isan interactive computer visualization and analysis environment for oceanographers and meteorologists analyzing large and complex gridded data sets. Detailed description is found at the Ferret home page, where an online-manual for the latest version can be found.
Specific features related to pyferret, i.e., new graphic capabilities and the integration of ferret and python are described at the pyferret home page.
Modules and program start
module avail ferret delivers a list of available versions. The desired version can be selected with environmental modules.
module load ferret/<version> selects the version and sets the path to ferret and to other ferret related binaries (i.e. Fpalette). The required Ferret environment variables are defined by the calling wrapper startup-script ferret itself. They become undefined when ferret is terminated. Do not specify them in your .bashrc.
ferret -h
delivers list of program options.
Special features of the HLRN installation
pyferret
Usage of the pyferret-package with your own python - environment will be enabled after installation of a stable python - version. The wrapper startup-script ferret starts pyferret.
Special go-Files, additional data sets
All additional files are in the directory /sw/viz/ferret/ferret_iow.
| Tool | scripts (use go/help <script> for help) |
|---|---|
| Median filter | median_l , median_test.jnl |
| Baltic Sea landmask | modified fland |
| Baltic Sea coastlines | land_balt_100, land_balt_200 |
| West-African coastlines | land_south |
| comfortable aggregation | aggregate |
The median filter is written by E. D. Cokelet. There is a test-script median_test.jnl.
For models of the Baltic Sea regional topographic data sets are compiled and formatted like the etopo data, but with 1 n.m. oder 2 n.m. resolution. For this reason go fland 2 or go fland 1 works too for the Baltic Sea area.
Specific palettes
Palettes adcplus.spk, adcpmin.spk and adcp.spk are suitable for visualisation of current fields oscillating around 0. Suitable for centered fill or shade levels.
Data set aggregation
Ferret allows to aggregate data distributed over many files into one logical data set.
- Aggregation related manual section
- Simplified aggregation over the time-dimension
For convinience, at HLRN the go-script aggregate can be used.
External functions
The dynamically linked versions of Ferret allow to include new functions as external functions. This has not been tested at HLRN.