U.S. GEOLOGICAL SURVEY
                WATER-RESOURCES INVESTIGATIONS REPORT 93-4076

                         HYDRO-CLIMATIC DATA NETWORK
                                    (HCDN)
                        STREAMFLOW DATA SET, 1874-1988

                  [This is the \DOCFILES\COPYFLOW.DOC file]

                             HOW TO USE COPYFLOW

         This document describes how to copy HCDN streamflow data from
      the HCDN CD-ROM to a hard disk using the program COPYFLOW.  Before
      using COPYFLOW, you should print a hard copy of this document.
      Save the hard copies for future reference.

         The COPYFLOW software runs only on a DOS computer system.  If
      you are using any computer system other than a DOS PC, the
      COPYFLOW software will not run on your system.  Please see the
      NON-DOS.DOC file.

         If you have not already done so, run the installation procedure
      by making the CD-ROM drive the active drive and typing INSTALL
      followed by pressing the Enter key.  Follow the on-screen
      instructions to complete the installation.  Once the installation
      is complete, start the GSMENU software by typing GSMENU, pressing
      the Enter key, and then pressing the F1 key for instructions on
      using GSMENU.

         COPYFLOW copies HCDN streamflow data to a user-specified file.
      The program first looks for a file named OUTPUT.FIX and verifies
      that that is the file from which the streamflow station numbers
      are to be obtained.  If it is not, you are queried for the correct
      file name.  Next, you are asked to specify the file in which the
      streamflow data is to be placed. Then you are asked the form of
      the data - ASCII or binary - and the time scale of the data -
      daily, monthly, or annual.  Finally, you are queried about the
      period of record desired.  The data is then copied to the file.

         To create the file containing the station numbers you may
      either run the GSSEARCH program and have it put the desired
      station numbers (STA_NUM) into a fixed length file or you may
      create an ASCII file containing the station numbers by any other
      means - such as a text editor.  The station numbers must be in the
      first eight columns one per line.  Leading zeros must be present.
      Anything in column nine or later is ignored.

         The file containing the station numbers may have any name.
      GSSEARCH, by default, creates a file called OUTPUT.FIX; although
      you may have GSSEARCH give the file a different name.

         COPYFLOW looks in your current directory for a file called
      OUTPUT.FIX.  If it finds such a file, it asks you if it should use
      that file for the station numbers.  If you say yes, it uses it.
      If you say no or if it doesn't find a file named OUTPUT.FIX,
      COPYFLOW asks you for the name of the file you want to read the
      station numbers from.  COPYFLOW verifies that it can find the file
      you have specified.  If it can, it uses it.  If it can't, it
      repeatedly asks you to give it a file name until it gets one it
      can find or you just press the Enter key to indicate that you want
      to quit.

         COPYFLOW next asks you for the name of the file to which you
      want the streamflow data copied.  COPYFLOW checks to see if the
      file you have specified already exists.  If it does not exist, it
      creates it and copies the streamflow data there.  If it does
      already exist, COPYFLOW asks you if you want the existing file
      overwritten.  If you say yes, COPYFLOW overwrites the contents of
      the existing file with the new streamflow data.  If you say no,
      COPYFLOW repeatedly asks you to give it a file name until it gets
      one which doesn't exist, one which does exist but you say can be
      overwritten, or you just press the Enter key to indicate that you
      want to quit.

         COPYFLOW then asks you if you want the data copied in either
      ASCII or binary form.  The ASCII is the plain text form and is
      probably what you want if you plan to work on the data with a text
      editor, print the data as is, or read it into most programs such
      as spread-sheets or statistical packages.  You also want the ASCII
      form if you are working on a machine which does not adhere to the
      IEEE representation of floating point numbers.  The binary form is
      the internal machine representation (IEEE format) of the data.  It
      is generally useful only to those who are writing their own
      programs to process the data and wish to avoid the overhead of
      converting ASCII data to the internal representation.  If you want
      the ASCII form of the data just press the Enter key (or press "1"
      followed by the Enter key).  If you want the binary form of the
      data press "2" followed by the Enter key.

         COPYFLOW next asks you if you want the annual means, maximums,
      and minimums, the monthly means, or the daily values.  Enter "1"
      for the annual values, "2" for the monthly values, or "3" for the
      daily values.

         COPYFLOW then asks you if you want all available years of
      streamflow data, a range of years of data, or a single year.
      Enter "1" for all available years, "2" for a range of years, or
      "3" for a single year.  If you select a range of years, you are
      asked to enter the starting and ending years.  If you select a
      single year, you are asked to enter that year.

         COPYFLOW now copies the streamflow data you have requested to
      the file you specified.  It copies each station, one at a time, to
      the file.  It keeps you informed of each station it is working on
      so you can follow its progress and it tells you how many years of
      data, if any, it copies for each station.  When it is done with
      all the stations, it tells you the total number of years it has
      copied.

         COPYFLOW copies the streamflow data in the exact format the
      data is stored on the CD-ROM.  See the files \HCDN\1ST_READ.ME and
      \HCDN\FORMATS\1ST_READ.ME for information on the formats of these
      files.  The particular files describing the formats according to
      the choices you made above are

                                 ASCII      binary
                      Annual    AAM.FMT     BAM.FMT
                      Monthly   AMM.FMT     BMM.FMT
                      Daily     ADV.FMT     BDV.FMT