NAME
tdds - Time-Dependent Data System for simulation models
ABSTRACT
A system of computer utilities and routines, collectively identified
as the Time-Dependent Data System (TDDS), has been developed and
documented by the U.S. Geological Survey. The TDDS is designed for
processing time sequences of discrete, fixed-interval, time-varying
geophysical data-in particular, hydrologic data. Such data include
various, dependent variables and related parameters typically needed
as input for execution of one-, two-, and three-dimensional
hydrodynamic flow/transport and associated water- quality simulation
models. Such data can also include time sequences of results
generated by numerical simulation models. Specifically, TDDS
provides the functional capabilities to process, store, retrieve,
and compile data in a Time-Dependent Data Base (TDDB) in response to
interactive user commands or preprogrammed directives. Thus, the
TDDS, in conjunction with a companion TDDB, provides a ready means
for processing, preparation, and assembly of time sequences of data
for input to models; collection, categorization, and storage of
simulation results from models; and intercomparison of field data
and simulation results.
The TDDS can be used to edit and verify prototype, time-dependent
data to affirm that selected sequences of data are accurate,
contiguous, and appropriate for numerical simulation modeling. It
can be used to prepare time-varying data in a variety of formats,
such as tabular lists, sequential files, arrays, graphical displays,
as well as line-printer plots of single or multiparameter data sets.
The TDDB is organized and maintained as a direct-access data base by
the TDDS, thus providing simple, yet efficient, data management and
access. A single, easily used, programmer's interface provides for
all access to and from a particular TDDB and, thus, enables all
storage or retrieval operations and is available for use directly
within models, other user-provided programs, and other data systems.
METHOD
The TDDB is an indexed, binary, direct-access file used to store
hydrologic, meteorologic, and water-quality data sets. The TDDB is
organized with an index that contains information defining each data
set, including type of data, station identifier, period of record,
processing date, and location the data set is stored in the TDDB.
Three storage/retrieval routines (DADIO, DADI, and DADO) provide the
communication link between the TDDS--as well as numerical-simulation
models or other user-application programs--and the TDDB. No other
ready means of direct access to the data base is necessary or
meaningful because data are maintained in the TDDB in a format
unique to these callable Fortran 77 storage/retrieval routines.
Access to the TDDB is additionally monitored and controlled by
information contained in a Data-Station Reference (DSR) file. This
file uniquely identifies, among other attributes, the geographical
location of the data-collection sites. The DADIO routines, TDDB,
and the DSR file (DSRFILE), when embedded in models, model
preprocessors, and (or) other user-developed application programs,
permit the extraction of data from, or the transfer of data to, the
TDDB. The Branch-network (BRANCH) unsteady flow model allows direct
access to the data stored in and can store computed results in a
TDDB.
HISTORY
Version 6.0 1997/03/06 - XYPLOT option added to allow plots of one
data set as a function of another data set for a single time
series. The DAPLOT option now has the capability to plot wind
vectors versus time or the present difference plot. If the wind
vector plot is selected, matching wind speed and wind direction
data is required from the TDDB. Negative wind speeds are set to
0. The time series of the selected data set must match the
requested wind data.
Version 5.2 1996/06/03 - Fixed interpretation of update codes
associated with Integer*2 stage data. Fixed Lahey F90 compiler
dependencies.
Version 5.1 1996/04/22 - WRDAPP release 3. Maximum number of data
sets increased from 465 to 476, seven new parameter type codes
added (BC, BS, AC, AS, V, W, and WZ), several parameter
definitions and type codes modified. Use water-surface elevation
instead of water level or stage. Fixed labeling of line-printer
plots for parameter definitions.
Version 4.8 1995/07/25 - Added options to plot data in from 1- to
9-day format. Removed block data dependencies. New date and
time routines. Bug fixes. Reordered main menu to reflect
processing order. Added query for the name of the master file.
File name that captures user responses to prompts named
TDDSLOG.DAT. Grouped routines in related code groups rather than
in separate files.
Version 2.4 1994/02/15 - Improved consistency of error messages and
date and time labeling, including version labeling, minor bug
fixes, and code cleanup. Support added for SWIFT2D estuarine
model input format.
Version 92/08/01 - Added output of WATSTORE unit values records and
corrected minor bugs.
Version 92/05/07 - First UNIX release, code cleaned up and made UNIX
compatible.
Version 92/03/02 - Allow selection of data sets by interactively
scanning the TDDB index.
Version 92/02/11 - Added data recording frequencies 8 and 12 values
per day to 24, 48, 96, 144, 240, 288, 720, and 1440 values per
day list.
Version 91/09/05 - First UNIX version.
Version 90/12/03 - Major change from 8-digit to 16-digit station
numbers, added capability to output data in SWIFT2D estuarine
model input format.
DATA REQUIREMENTS
Input data consists of time series of data as obtained from field
measurements, computer simulations, applications programs, and other
data base systems, such as WATSTORE data and program-control data,
such as date and time, station names, data frequency, data type, and
program options.
OUTPUT OPTIONS
The system provides numerous output options that format the data
stored in the TDDB in various formats as tabular lists, sequential
files, and digital and line-printer plots. Sequential files can be
output in program-default, user-specified, WATSTORE daily-values,
WATSTORE unit-values, or model-specific formats.
SYSTEM REQUIREMENTS
TDDS is written in Fortran 77 with the following extensions: use of
integer*2 declarations, use of include files, variable names longer
than 6 characters, and reference to compiler-dependent system date
and time routines. TDDS requires a utility library (libutl) that
includes the software/user, software/computer, software/data base,
and software/graphics interaction routines. TDDS graphics are coded
using CalComp graphics calls. The libutl software provides graphics
libraries to convert CalComp graphic references to Graphical Kernel
System (GKS) library references and Interactive Software Services's
INTERACTER library references. Generally, the program is easily
installed on most computer systems that have access to one of the
mentioned graphics libraries. The code has been used on UNIX-based
computers and DOS-based 386 or greater computers having a math
coprocessor and 4 mb of memory.
DOCUMENTATION
Regan, R.S., Schaffranek, R.W., and Baltzer, R.A., 1996, Time-
Dependent Data System (TDDS)--An interactive program to assemble,
manage, and appraise input data and numerical output of
flow/transport simulation models: U.S. Geological Survey Water-
Resources Investigations Report 96-4143, 104 p.
REFERENCES
Bower, D.E., Sanders, C.L., Conrads, P.A., 1993, Retention time
simulation for Bushy Park Reservoir near Charleston, South
Carolina: U.S. Geological Survey Water-Resources Investigations
93-4079, 47 p.
Goodwin, C.R., 1991, Simulation of the effects of proposed tide
gates on circulation, flushing, and water quality in residential
canals, Cape Coral, Florida: U.S. Geological Survey Open File
Report 91-237, 43 p.
Lai, C., Schaffranek, R.W., and Baltzer, R.A., 1978, An operational
system for implementing simulation models, a case study: American
Society of Civil Engineers Seminar on Computational Hydraulics at
the 26th Annual Specialty Conference of the Hydraulics Division,
University of Maryland, College Park, Md., p. 415-454.
Lipscomb, S.W., 1989, Flow and hydraulic characteristics of the
Knik-Matanuska River Estuary, Cook Inlet, Southcentral Alaska:
U.S. Geological Survey Water-Resources Investigations Report
89-4064, 52 p.
Schaffranek, R.W., and Baltzer, R.A., 1978, Fulfilling model time-
dependent data requirements: American Society of Civil Engineers
Symposium on Technical, Environmental, Socioeconomic, and
Regulatory Aspects of Coastal Zone Management, Coastal Zone '78,
v. III, p. 2069-2084.
TRAINING
Implementation and Calibration of Unsteady Open-Channel Flow
Transport Models (SW3091TC), offered annually at the USGS National
Training Center.
CONTACTS
Operation and Distribution:
U.S. Geological Survey
Hydrologic Analysis Software Support Program
437 National Center
Reston, VA 20192
h2osoft@usgs.gov
Official versions of U.S. Geological Survey water-resources analysis
software are available for electronic retrieval via the World Wide
Web (WWW) at:
http://water.usgs.gov/software/
and via anonymous File Transfer Protocol (FTP) from:
water.usgs.gov (path: /pub/software).
The WWW page and anonymous FTP directory from which the TDDS
software can be retrieved are, respectively:
http://water.usgs.gov/software/tdds.html
--and--
/pub/software/general/tdds
--and--
/pub/software/general/libutl
SEE ALSO
branch(1) - One-dimensional Branch-network flow model
libutl(1) - Utility libraries for simulation models
swift2d - Surface-Water Integrated Flow and Transport
model in Two Dimensions