DATALIST

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lists data elements of a Midas, Text, or binary file

<FILE>   Midas data, Text, or binary file to list
<START>  Offset of first element or line to list (0..n) A negative number
         indicates a position relative to the end of the file. A fractional
         number will be converted to the floor of the fraction when not in
         Abscissa mode. 
<NELEM>  Number of elements to list. [DEF=32; if START<0 DEF=list to EOF]
<ABSC>   Index or Abscissa mode for <START> and <NELEM> parameters [DEF=INDEX]
<FORM>   Override the format in the file

This routine lists the specified range of a Midas data file, Text file, binary
file to the terminal. If the file handler supports advanced listing of the file
by implementing the ListFile interface, it's data can also be listed based on
the file handler's implementation (e.g. CSV, DBF, JAR, TAR, ZIP are supported).

The /NC=n or number of columns switch can be used to set the number of columns
of data in the output display.  By default, the number of columns is set to
the maximum number of elements of the particular data type that can be
displayed in an 80 character window.

Since NeXtMidas 2.7.0, unknown file types or files with the FG=RAW qualifier
will be printed in a hexdump-compatible format with HEX and ASCII values shown.
This feature is only enabled if <FORM> is not specified.

Since NeXtMidas 2.9.0, a negative number can be given for the START. This will
indicate that the user wishes to show the 'tail end' of the data (i.e. all the
data from (EOF-START) to EOF, unless NELEM is specified).

Since NeXtMidas 2.9.0, an abscissa can be given for the START. Abscissa is 
indicated by either using the tilde ('~') at the beginning of the number given 
in START or by using ABSC=true. 

Examples:
  1. List data of a Type 1000 file (CF) starting from the 10th element and using
     one column per data element.
      nM> datalist nxm.sys.dat.sinewave.prm 9 /nc=1

  2. List first ten (10) data elements (frames) of a Type 2000 file:
      nM> datalist nxm.sys.dat.apenny.prm 0 10

  3. List data records of a Type 3000 file
      nM> datalist nxm.sys.dat.test3000.prm

  4. List data records of a Type 5000 file
      nM> datalist nxm.sys.dat.sv1.prm

  5. List data records of a Type 6000 file
      nM> datalist nxm.sys.dat.test6000.prm

  6. Show the first two (2) lines of a text file:
      nM> datalist nxm.sys.dat.cities.txt 0 2

  7. Show the last fifty lines in a text file
      nM> data nxm.sys.dat.cities.txt -50

  8. Show the last 20 lines of a text file (starting 50 from the EOF).
      nM> data nxm.sys.dat.cities.txt -50 20

  9. Show the last 5 elements (bytes) in an image (binary) file:
      nM> data nxm.sys.dat.Sunset.jpg -5

 10. Show the first four data records in an DBF (database) file:
      nM> data nxm.sys.dat.world.dbf ,, 4

 11. Show the data records in an CSV (text database) file:
      nM> data nxm.sys.dat.airports.csv
      
 12. Show the value of the third piece of data in a Type 1000 file 
     (with a start of 100.0 and a delta of .1) 
      nM> data junk1000 ~100.2 nelem=1
            -or -
      nM> data junk1000 START=100.2 NELEM=1 ABSC=ABSC

Switches:
  All Files:
    /L   - Show data element positions of data in file (0..n). [DEFAULT=TRUE]
           For text file this is the line number.
    /SW= - TBD - screen width
  Data Files ONLY:
    /ABS - TBD - show abscissa value for each line
    /BIN - display data file in binary format
    /H   - display data file header as well
    /HEX - display data files in hexadecimal format
    /K   - display data file keywords as well
    /NC= - number of columns (1000/2000 only)
    /NW= - DEPRECATED - Use /SW
    /P   - display data file packet headers
    /SW= - limit the screen width [DEF=computed internally]