bfloat(sqrt(%i))?



Am Freitag, den 30.10.2009, 14:05 -0400 schrieb Raymond Toy:
> With current CVS, we get 1.0b0*(-1)^(1/4).
> 
> But in 5.17, bfloat(sqrt(%i)) -> 7.071067811865475b-1 %i +
> 7.071067811865475b-1
> 
> Shouldn't bfloat(sqrt(%i)) give a bfloat result?
> 
> We have similar problems with float(sqrt(%i)).

Yes, I think so too. 
Two more problems with float and bfloat are:

(%i28) bfloat((1+%i)^2);
(%o28) (%i+1.0b0)^2

(%i29) float((1+%i)^2);
(%o29) (%i+1.0)^2

It does not even help to use only float or bigfloat numbers:

(%i34) bfloat((1.0b0+1.0b0*%i)^2.0b0);
(%o34) (1.0b0*%i+1.0b0)^2.0b0

(%i35) float((1.0+1.0*%i)^2.0);
(%o35) (1.0*%i+1.0)^2.0

Dieter Kaiser