rpt34
Report 34: EzGet: A Library of Fortran Subroutines
to Facilitate Data Retrieval
Taylor, Karl E.
April 1996, 70 pp.
The software described in this document is designed to facilitate retrieval
of modeled and observed climate data stored in popular formats including
DRS, netCDF, GrADS, and, if a control file is supplied, GRIB. You can specify
how the data should be structured and whether it should undergo a grid
transformation before you receive it, even when you know little about the
structure of the stored data (i.e., its dimension order, grid, and domain).
The software is referred to here as EzGet (pronounced "easy-get") and
it comprises a set of subroutines that can be linked to any FORTRAN program.
EzGet reads files through the cdunif interface which is available from
the Program for Climate Model Diagnosis and Intercomparison (PCMDI), but
use of EzGet does not require familiarity with cdunif. The main advantages
of using this software instead of the lower level cdunif library include:
- Substantial error trapping capabilities and detailed error messages
- Versatile capability of conveniently selecting data from specified regions
(e.g., oceans, North America, all land areas north of 45 degrees latitude,
etc.)
- Ability to map data to a new grid at the time it is retrieved by EzGet
- Automatic creation of "weights" for use in subsequent averaging or masking
of data
- Increased control in specifying the domain, grid and structure of the
retrieved data.
Taken together these capabilities will simplify the process of writing
programs for accessing data stored in different formats and structures,
including all the observed data sets and the model output from various
model intercomparison projects (AMIP, PMIP, CMIP, etc.) archived at PCMDI.
EzGet software and the latest version of this document are available
through the PCMDI web site: http://www-pcmdi.llnl.gov/ktaylor/ezget/ezget.html
For a pdf version of this document go to (pdf
file)
UCRL-MI-123395