The  pause command displays any text associated with the command and
 then waits a specified amount of time or until the carriage return is
 pressed.   pause is especially useful in conjunction with  load files.

 Syntax:
         pause  {""}

  may be any integer constant or expression. Choosing -1 will
 wait until a carriage return is hit, zero (0) won't pause at all, and
 a positive integer will wait the specified number of seconds.

 Note: Since  pause is not part of the plot it may interact with
 different device drivers differently (depending upon how text and
 graphics are mixed).

 Examples:
         pause -1    # Wait until a carriage return is hit
         pause 3     # Wait three seconds
         pause -1  "Hit return to continue"
         pause 10  "Isn't this pretty?  It's a cubic-spline."