plot2d (?) error



> 
> I can make a list of points and display it, but plot2d is ( or should be 
> ) simpler.
> 
> Adam

(%i8) Plot2DDiscrete(x,xMin,xMax):=
block(
xx:makelist(i,i,xMin,xMax),
yy:map(f,xx),
load(draw),
draw2d(
        point_type    = filled_circle,
        point_size    = 3,
        points_joined = false,
        color         = blue,
        key           = "punkty",
            points(xx,yy),
        terminal      = 'screen)


)$(%i9) Plot2DDiscrete(x,1,10);(%o9) [gr2d(points)]


This function draws discrete points (x,y:f(x)),

How to pass external function thru parameters ?
( here f is global function )

Adam