Water Resources Applications Software

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Summary of TDDS

       tdds - Time-Dependent Data System for simulation models

       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.

       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

       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

       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

       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.

       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.

       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.

       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.

       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.

       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.

       Implementation and Calibration of Unsteady Open-Channel Flow
       Transport Models (SW3091TC), offered annually at the USGS National
       Training Center.

       Operation and Distribution:
          U.S. Geological Survey
          Hydrologic Analysis Software Support Program
          437 National Center
          Reston, VA 20192

       Official versions of U.S. Geological Survey water-resources analysis
       software are available for electronic retrieval via the World Wide
       Web (WWW) at:


       and via anonymous File Transfer Protocol (FTP) from:

         (path: /pub/software).

       The WWW page and anonymous FTP directory from which the TDDS
       software can be retrieved are, respectively:


       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

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