Name

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      DBXVAL

Purpose

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      Quickly return a value of the specified item number

Explanation

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      Procedure to quickly return a value of the specified item number
      from the entry.

Calling Sequence

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      result = dbxval( entry, idltype, nvalues, sbyte, nbytes )

Inputs

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      entry - entry or entries from data base (bytarr)
      idltype - idl data type (obtained with db_item_info)
      nvalues - number of values to return (obtained with db_item)
      sbyte - starting byte in the entry (obtained with db_item)
      nbytes - number of bytes (needed only for string type)
                      (obtained with db_item)

Outputs

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      function value is value of the specified item in entry

Keywords

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      bswap - If set, then IEEE_TO_HOST is called.

Restrictions

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      To increase speed the routine assumes that entry and item are
      valid and that the data base is already opened using dbopen.

Revision History

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      version 0 D. Lindler Nov. 1987 (for new db format)
      Version 1, William Thompson, GSFC, 28 March 1994.
                      Incorporated into CDS library.
      Version 2, Richard Schwartz, GSFC/SDAC, 23 August 1996
                      Allowed Entry to have 2 dimensions
      Version 2.1, 22 Feb 1997, JK Feggans,
                              avoid reform for strings arrays.
      Version 2.2 Use overwrite with REFORM(), W. Landsman, May 1997
      Converted to IDL V5.0 W. Landsman September 1997
      Work for multiple-valued strings W. Landsman October 2000
      Add new 64bit & unsigned integer datatypes W.Landsman July 2001
      Version 3, 2-May-2003, JK Feggans/Sigma, W.T. Thompson
          Added BSWAP keyword to avoid floating errors on some platforms.