| Unsophisticated interface to a running gnuplot program.    This represents a running gnuplot program and the means to
    communicate with it at a primitive level (i.e., pass it commands
    or data).  When the object is destroyed, the gnuplot program exits
    (unless the persistoption was set).  The communication is
    one-way; gnuplot's text output just goes to stdout with no attempt
    to check it for error messages.     Members:
        gnuplotthe pipe to the gnuplot command.     Methods:
        __init__start up the program.        __call__pass an arbitrary string to the gnuplot program,
            followed by a newline.        writepass an arbitrary string to the gnuplot program.        flushcause pending output to be written immediately. 
        
            | Methods |  |  
        | __call__ __init__
 
 |  
            |  | __call__ |  
        | 
__call__ ( self,  s )
 Send a command string to gnuplot, followed by newline. |  
            |  | __init__ |  
        | 
__init__ ( self,  persist=None )
 Start a gnuplot process.        Create a GnuplotProcessobject.  This starts a gnuplot
        program and prepares to write commands to it.         Keyword arguments:
          persist=1start gnuplot with the -persistoption,
              (which leaves the plot window on the screen even after
              the gnuplot program ends, and creates a new plot window
              each time the terminal type is set tox11).  This
              option is not available on older versions of gnuplot. 
        
            | Exceptions |  |  
        | ( '-persist does not seem to be supported ' 'by your version of gnuplot!' ) 
 |  |  |