Re: Tcl precision [was: Re: [Plplot-devel] Java changes to support plsurf3d()]

[Joao C. <jc...@fe...>]

On Wednesday 16 October 2002 04:02, Maurice LeBrun wrote:
> Joao Cardoso writes:
>  > On Tuesday 15 October 2002 23:07, Maurice LeBrun wrote:
>  > > | The story becomes more interesting.  I believe the two
>  > > | representations (variable or tclMatrix) would've given the same
>  > > | result in pre-Tcl8.0. The reason being that in the old Tcl,
>  > > | "everything's a string".  But no longer -- the variable that you
>  > > | create with "set" is "dual-ported", meaning it has both a binary=
 and
>  > > | string representation.  The binary one is used in expression
>  > > | evaluations and so is more accurate.
>  >
>  > But this means that it is single precision, doesn't it? Tcl is build
>  > with floats or doubles? So, if the default is float, as I supose, we
>  > shouldn't compare plots made with the tcl front-ends with plots made
>  > from frontends compiled with doubles. It is not the device driver th=
at
>  > matters, but the origin of the data -- floats in, say, x08.tcl with
>  > doubles in x08c. And I think to remember from Alan's e-mail (that I =
dont
>  > have at the moment) that he was using plplot compiled with doubles.
>
> Tcl uses double internally.  But the precision when printing them out
> defaults to 12.

Thanks.
Joao