Problems with map.



Thank you so much.  That makes perfect sense now.

Regarding your last point:

if atom(1/2) then return "all my underlying problems would go away.....";

Chris


From: Richard Fateman [mailto:fateman at eecs.berkeley.edu]
Sent: 26 September 2012 19:32
To: Christopher Sangwin
Cc: maxima at math.utexas.edu
Subject: Re: [Maxima] Problems with map.

On 9/26/2012 11:17 AM, Christopher Sangwin wrote:
(%i2) map(f,1/2);
                        1
map: improper argument: -
                        2
-- an error. To debug this try: debugmode(true);

What result did you want?   f(1)/f(2) ?

The internal operator in 1/2 is 'rat'  which requires 2 integer operands.  A special case
could be set to create f(1)/f(2)   which is really f(1) *  f(2)^(-1) in this example, but
I'm not sure that map should do that.

Or did you want f(1/2)?

Or now that you have an explanation, is the behavior OK with you?


But

(%i3) atom(1/2);
(%o3)                                false

Actually, I think that 1/2 is "a number"  and thus atom(1/2) should be true.  But this atom
concept is not very accurately portrayed. Atoms should be non-decomposable, except
by nuclear fission..
RJF