Not only this. We have also
limit(1/zeroa-1/zeroa) => 0
I.e. zeroa is the certain infinitesimal while usually in mathematics
o(1) is equivalence class of infinitesimals.
I think that erf(inf)=1 and atan(inf)=%pi/2, but 0*inf is 0*inf and not
0. Similarly, inf-inf is inf-inf, not 0.
Another question whether we should assume that inf-inf=inf+minf. I think
that is(inf-inf=inf+minf)=>false, but is(equal(inf-inf,inf+minf))=>true.
I'm sorry that interfered.
23.05.2012 7:46, Raymond Toy ?????:
> As mentioned a few days ago, maxima automatically simplifies erf(inf) to
> 1. And also atan(inf) to %pi/2. This seems intentional, but can lead
> to interesting things like
>
> (atan(inf)-%pi/2)*inf => 0
> but
> limit(atan(x)-%pi/2)*x,x,inf) => -1
>
> as Stavros mentioned.
>
> Therefore, I think we should change this behavior so that erf(inf) is
> erf(inf) and not 1.
>
> But since this seems intentional, I'm soliciting opinions on this. This
> also affects erfc, erfi, gamma_incomplete, fresnel_s and fresnel_c.
> There might be others as well.
>
> Ray