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(gnuplot.info)binary

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Enter node , (file) or (file)node

 `splot` (Note: splot ) can read binary files written with a specific format
 (and on a system with a compatible binary file representation.)

 In previous versions, `gnuplot` (Note: gnuplot ) dynamically detected binary
 data files.  It is now necessary to specify the keyword `binary` directly
 after the filename.

 Single precision floats are stored in a binary file as follows:

       <N+1>  <y0>   <y1>   <y2>  ...  <yN>
        <x0> <z0,0> <z0,1> <z0,2> ... <z0,N>
        <x1> <z1,0> <z1,1> <z1,2> ... <z1,N>
         :      :      :      :   ...    :

 which are converted into triplets:
       <x0> <y0> <z0,0>
       <x0> <y1> <z0,1>
       <x0> <y2> <z0,2>
        :    :     :
       <x0> <yN> <z0,N>

       <x1> <y0> <z1,0>
       <x1> <y1> <z1,1>
        :    :     :

 These triplets are then converted into `gnuplot` iso-curves and then
 `gnuplot` proceeds in the usual manner to do the rest of the plotting.

 A collection of matrix and vector manipulation routines (in C) is provided
 in `binary.c`.  The routine to write binary data is

       int fwrite_matrix(file,m,nrl,nrl,ncl,nch,row_title,column_title)

 An example of using these routines is provided in the file `bf_test.c`, which
 generates binary files for the demo file `demo/binary.dem`.

 The `index` (Note: index ) keyword is not supported, since the file format
 allows only one surface per file.  The `every` (Note: every ) and  `using`
 (Note: using ) filters are supported.  using operates as if the data were
 read in the above triplet form.