9 Mar
2006
9 Mar
'06
5:31 p.m.
"CD" == Chris Dams <Chris.Dams@mi.infn.it> writes: CD> ignored. Furthermore step(0)=1/2. This, however, should not be CD> taken too seriously as there is also the automatic evaluation CD> step(x)^2 -> step(x).
For a bigger consistency I would prefer to have either step(0)=0 or step(0)=1. Such a small features which is easy to overlook sometimes takes hours to realise. If three-values are really needed we may have another function sign(x)=1, x>0 sign(x)=0, x=0 sign(x)=-1, x<0 with the property sign(x)^3 -> sign(x). The current step(x) is then (sign(x)+1)/2. Best wishes, Vladimir -- Vladimir V. Kisil email: kisilv@maths.leeds.ac.uk -- www: http://maths.leeds.ac.uk/~kisilv/