var - the cmusic var command

The cmusic var command has the general format:

       var T NAME LIST ;

where: 
    T    is an action time, 
    NAME is the name of the variable to be set, and 
    LIST is one or more values for the variables.

NAME may be any of:

    pN or p[N] - refers to note parameter N (N may be an expression if 
		 it is enclosed in square brackets []);
    vN or v[N] - refers to global numerical variable N (N may be an 
		 expression if it is enclosed in square brackets []);
    sN or s[N] - refers to global string variable N (N may be an expression 
		 if it is enclosed in square brackets []).

LIST values may be either numeric (for "p" or "v" variables), or
strings enclosed in double quote (") marks.  The first value given
replaces the value of the variable named.  Succeeding values replace
successive variables.  Variables may be used in cmusic expressions such
as global values, or in various special ways, such as to set filenames
for the sndin unit generator, or to set the score tempo via the "set
tempowith" command;

Examples:

   var 0 p5 33;         {Sets p5 to 33 at time 0}
   var 0 p5 33 44;      {Sets p5 to 33 and p6 to 44 at time 0}
   var 0 v[v3/2] 19Hz;  {If variable v3 is equal to 15, then this
			 statement sets v7 to 19Hz}
   var 0 s1 "filename1" "filename2";
			{sets string variable s1 to "filename1" and
			 s2 to "filename2"}
