Re: [Matplotlib-users] Re: new scientific notation format

[Darren D. <dd...@co...>]

On Tuesday 03 May 2005 10:02 am, Humufr wrote:
> I tried the new notation and I think it's good but sometimes the result
> is not so good. For example with the plot ( plot(x+2e10, -x+2e6) ) I
> have a: +1.99999e6 for the y scale and it's not exactly the goal of this
> change I think.
> But good idea for this change.
>

This was by design. I had a version at one point that would have looked lik=
e=20
this for your example:

=A0----------------------------------------------
=A0 -5 =A0 =A0 =A0 -4 =A0 =A0 =A0 =A0-3 =A0 =A0 =A0 -2 =A0 =A0 =A0 -1 =A0 =
=A0 =A0 =A00
=A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0=
 =A0  x1e5+2e10=20

I didnt want positive data to have negative ticklabels, I think it is more=
=20
important to understand the plot at a glance, even if it results in an ugly=
=20
offset. What really settled the issue in my mind is that you can always fin=
d=20
a case that produces an ugly offset, for example:=20
plot(arange(0,1e5,1e4)+7.777777777e15). When you consider zooming the plot=
=20
and panning the plot, there needs to be a consistent method to determine th=
e=20
offset, otherwise the ticklabels could switch from positive or negative whi=
le=20
you navigate.

in ticker.py, you can set useOffset in ScalarFormatter.__init__() to False,=
=20
which would give you more or less the current behavior:

 ----------------------------------------------
   2        2         2        2        2        2
                                                 x1e10=20

With the new default behavior (useOffset=3DTrue), if you don't like the off=
set,=20
you can at least interpret your data and decide how to process it in order =
to=20
generate a more acceptable plot.

Thank you for pointing this out.

=2D-=20
Darren S. Dale

Bard Hall
Department of Materials Science and Engineering
Cornell University
Ithaca, NY. 14850

dd...@co...