Re: [office] surface plots

["Andreas J. Guelzow" <aguelzow@pyrshep.ca>]

Hi Eike,

On Wed, 2009-07-22 at 21:37 +0200, Eike Rathke wrote:
> Hi Andreas,
> 
> On Wednesday, 2009-07-15 10:39:57 -0600, Andreas J. Guelzow wrote:
> 
> > Regarding chart:class specified plots:
> > 
> > surface – The values of multiple <chart:series> (marked as being of type
> > chart:surface) are interpreted as a 'altitude' at a specific grid
> > location. The graph may visualize these using colors for height
> > intervals, creating color bands.
> > 
> > do I understand this as:
> > <chart:series chart:values-cell-range-address="S1.$C$1:S1.$C$16">
> >     <chart:domain table:cell-range-address="S1.$A$1:S1.$A$16"/>
> >     <chart:domain table:cell-range-address="S1.$B$1:S1.$B$16"/>
> > </chart:series>
> > 
> > or
> > 
> > <chart:series chart:values-cell-range-address="S1.$A$1:S1.$A$16" />
> > <chart:series chart:values-cell-range-address="S1.$B$1:S1.$B$16" />
> > <chart:series chart:values-cell-range-address="S1.$C$1:S1.$C$16" />
> > 
> > where C1 gives the altitude at x=A1, y=B1 or 
> > 
> > even as something else.
> 
> Seems "something else" is it.. Here's the answer of Chart implementer
> Ingrid Halama:

I figured out that probably "something else" was meant, in fact
something like Ingrid described. 

> 
> ---%<---snip---%<---
> 
> Neither of them. Hm, I think this needs to be specified more precisely. 

I think this is important to do, especially since if this is what
OpenOffice implements then it differs from other implementations.

> It should be understood as:
> 
> <chart:series chart:values-cell-range-address="S1.$A$1:S1.$A$16" />
> <chart:series chart:values-cell-range-address="S1.$B$1:S1.$B$16" />
> <chart:series chart:values-cell-range-address="S1.$C$1:S1.$C$16" />
> <chart:series chart:values-cell-range-address="S1.$D$1:S1.$D$16" />

This seems to be unnecessarily complicated. Since these series all
belong together wouldn't it make more sense to record them as
<chart:series chart:values-cell-range-address="S1.$A$1:S1.$D$16" />
Otherwise we introduce and artificial dissymmetry between the base
coordinates.

> 
> where A1 gives the altitude (y coordinate) at x=1, z=1
> and A2 gives the altitude at x=2, z=1
> and B1 gives the altitude at x=1, z=2
> and B2 gives the altitude at x=2, z=2
> and D3 gives the altitude at x=3, z=4
> ...
> 
> Let me try to give a more precise description for the specification:

This specification may describe OpenOffice's implementation but differs
from Gnumeric's implementation. I don't know how other implementors have
chosen to understand the description.

Andreas 

> --------
> surface – The values of multiple <chart:series> (marked as being of type 
> chart:surface) are interpreted as a 'altitude' at a specific grid 
> location. The graph may visualize these using colors for height 
> intervals, creating color bands.
> In case of chart:three-dimensional="true" a left handed three 
> dimensional cartesian coordinate system is used. The given values for a 
> series are interpreted as y-coordinates (representing the 'altitude'). 
> The accessory x-coordinates are generated from the positions in the 
> altitude-value sequence starting with 1.0. The first altitude value gets 
> an x value 1.0. The second altitude value is associated with an x value 
> of 2.0 and so forth. The z-coordinates are generated from the positions 
> of the series elements starting with 1.0. The first series has an 
> associated z coordinate of 1.0. The second series has a z-coordinate 2.0 
> and so forth.
> In case of chart:three-dimensional="false" each altitude value is 
> located on a Cartesian x-/y-grid. The x-coordinates are generated from 
> the positions in the altitude-value sequence starting with 1.0. The 
> y-coordinates are generated from the positions of the series elements 
> starting with 1.0.
> ------
> 
> A real 3D plot with coordinates x, y and z per series is not specified 
> so far. But that is an interesting candidate for the future.
> 
> ---%<---snap---%<---
> 
-- 
Andreas J. Guelzow <aguelzow@pyrshep.ca>