Edwin Woollett pisze:
> On Dec. 1, 2008, Adam Majewski wrote:
>
>> (%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)
>>
>>
>> )$(%i9) Plot2DDiscrete(x,1,10);(%o9) [gr2d(points)]
>>
>>
>> This function draws discrete points (x,y:f(x)),
>>
>> How to pass external function thru parameters ?
>> ( here f is global function )
>>
>
> Why not use a Maxima "expression" with your listplot rather
> than a Maxima "function"?
>
> For example, the following listplot1 accepts either an
> expression or a (official) Maxima function:
>
> (%i1) display2d:false$
> /* load draw once, not every time you
> run listplot */
>
> (%i2) load(draw)$
> /* here is a version close to yours in
> spirit */
>
> (%i3) listplot1(expr,var,v1,v2):=
> block([xx,f,yy,i],
> xx:makelist(i,i,v1,v2),
> define(f(var),expr),
> yy:map(f,xx),
> draw2d(
> point_type = filled_circle,
> point_size = 2,
> points_joined = false,
> color = blue,
> key = "pts",
> points(xx,yy),
> terminal = 'screen) )$
>
> /* here we use listplot1 with a Maxima
> expression: */
> (%i4) listplot1(x^3,x,0,10)$
>
> /* here we use listplot1 with a Maxima
> function */
>
> (%i5) g(x):= x*sin(x)$
> (%i6) listplot1(g(y),y,0,10)$
>
> Ted Woollett
Thx. (:-)
Adam