[Date Prev] | [Thread Prev] | [Thread Next] | [Date Next] -- [Date Index] | [Thread Index] | [List Home]
Subject: Re: [office] surface plots
On Tue, 2009-07-28 at 17:09 +0200, Ingrid via Eike Rathke wrote: > >> The attribute > >> chart:deep has to be set to true in this case. The given values for a > >> series are interpreted as y-coordinates (representing the 'altitude'). > >> > > (As mathematician, I find it quite unusually to call the height y rather > > than z) > > > As physician I can't find anything unusual here. I not intending to offend but I think this issue falls more within Mathematics than Medicine. In any case, at least in North America (and I am pretty sure also in Germany 25 years ago) the z-axis would usually be used for height with x and y for the base. See for example http://reference.wolfram.com/mathematica/tutorial/ThreeDimensionalSurfacePlots.html http://www.omatrix.com/manual/mesh.htm http://homepages.see.leeds.ac.uk/~lecjm/Teaching/IDL_course/Notes/notes/node27.html > ---------------------------- > 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 with horizontal x axis > and vertical y axis (before any 3D scene transformations). 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 > categories element can be used to define labels for the x axis. The > first altitude value in each series 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. The series > names are used as labels at the z axis. > In case of chart:three-dimensional="false" each altitude value is > located on a 2 dimensional Cartesian coordinate system with horizontal x > axis and vertical y axis. The categories element can be used to define > labels for the x axis. 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. The series names are used as labels at the y axis. A > third axis element with chart:dimension="z" is used to define the range > and separation for the altitude values. In this case the thought > coordinate system should be right-handed. > ---------------------------- I really have a problem with this. If we use the same chart:class=chart:surface for contour and surface plots then the common axes should carry the same meaning, so we really shouldn't have y be the altitude in one and one of the base axes in the other. Moreover the two non-altitude variables should really be symmetric, ie. virtually interchangeable. Moreover non-ordinal labels should not used in such a plot since for the reader of such graphs an ordering is implied. Not ethat for only 2 visible axes it does not make sense to talk about right or left handed coordinate systems. > > I hope we can come together somewhere. It really would be good to have > this more detailed as it is within the current spec draft! > Let me know your suggestions! > I would think along the following line: surface -- this class of charts is used for surface and contour charts. A single series specifies a rectangular table cell area. Each column of this area corresponds to a specific x-value while each row corresponds to a specific y-value. The cell at the intersection of the column and row gives the altitude (z-value) at the specific location. The x-values are specified as the first chart:domain. If no chart:domain is given they default to 1 for the first column, 2 for the second column, etc. The y-values are specified as the second chart:domain. If no or only one chart:domain is given they default to 1 for the first row, 2 for the second row, etc. In case of chart:three-dimensional="false" a contour map is shown. Each altitude value is located on a 2 dimensional Cartesian coordinate system with horizontal x axis and vertical y axis. Axis elements with dimension 'x' and 'y' are used to desribe the visible axes. A third axis element with chart:dimension="z" is used to define the range and separation for the colours representing the altitude ranges. In case of chart:three-dimensional="true" a 3-dimensional surface plot is shown in a right handed coordinate system with 3 axes of dimensions 'x', 'y' and 'z'. (In this case we would need some specification method for the view point and view direction.) Andreas -- Andreas J. Guelzow Concordia University College of Alberta
[Date Prev] | [Thread Prev] | [Thread Next] | [Date Next] -- [Date Index] | [Thread Index] | [List Home]