ahmilb@houu64$bhpwriteseq

 bhpwriteseq < stdin filename=fname [optional parameters]        

 bhpwriteseq writes a BHPIO "sequential" dataset, which can be 

 randomly accessed by bhpread. The orders in which bhpread can read

 the dataset are defined by up to 5 trace-header keys which are  

 saved when bhpwriteseq creates the dataset. The sequential term 

 refers to the way in which the trace-header key index is written.

 The user does not have to have any knowledge about the trace-header

 values in the data. Contrast with bhpwritecube, which requires  

 the user to define a n-dimensional cube for holding trace header

 values. bhpwriteseq is useful when the limits of the data being 

 processed are not well-defined. However, bhpwritecube is        

 significantly more efficient and uses less system resources than

 bhpwriteseq.                                                    

 Required Parameters:                                            

  filename=fname        File name                                 

      Complete filenames are formed as path/filename_part-num    

      where part-num is a 4-digit partition number               

      EXAMPLE:                                                   

        Suppose pathlist=paths.dat, filename=offset-gathers,     

        and paths.dat consists of:                               

        /data/D_170_005                                          

        /data/D_169_001                                          

        /data/D_169_003                                          

        Filenames will be /data/D_170_005/offset-gathers_0001,   

                          /data/D_169_001/offset-gathers_0002,   

                          /data/D_169_003/offset-gathers_0003,   

                          /data/D_170_005/offset-gathers_0004,   

        ... until all data are written                           

 Optional Parameters:                                            

    pathlist='filename'.dat  ASCII file containing list of paths 

                             to use                              

    verbose=0                For debug print                     

    stripe=[yes,no]          Whether to create multiple partitions

    size=1999                Size of each file partition(stripe=yes)

    key1=fldr,R,1            First key, type, increment          

    key2=offset,I,50         Second key, type, nominal increment 

    key3=...                 Third key, type, increment          

    key4=...                 Fourth key, type, increment         

    key5=...                 Fifth key, type, increment          

    properties=...           List of ROFF properties             

                             If the input data were created by   

                             bhproffread, properties should be a 

                             list of the properties which        

                             were extracted

    horizons=...             List of horizons, if input data were

                             created by bhphorizon.              

    stdin_endian=2           Default endianness for data from stdin is NATIVE,

                             where NATIVE is the endianness of the platform

                             on which bhpwriteseq is running

                             Specify stdin_endian=0 to read LITTLE_ENDIAN from stdin

                             Specify stdin_endian=1 to read BIG_ENDIAN from stdin

    endian=native            Omit endian parameter to write native

                             Specify endian=1 to force BIG_ENDIAN

                             Specify endian=0 to force LITTLE_ENDIAN

    units=                   0=Seconds, 1=Feet, 2=Meters. If unspecified, the first trace

                             is checked. If dt/1000 > 8, units=2 is used.

                             If dt/1000 <= 8, units=0 is used. The units value is saved

                             in the header file for bhpread to use if required.

 EXAMPLE: Write 3D gathers, saving line, trace, and offset header

          keys.                                                  

 segyread tape=gathers.sgy |                                     

 bhpwriteseq filename=lines3014-3025 key1=ep,R,1 key2=cdp,R,1 \ 

   key3=offset,I,50                                              

 Contents of lines3014-3025.dat:                                 

  /hou/data/D_169_005/trinidad                                    

  /hou/data/D_170_003/trinidad