RE: .csv file

• To: Michelle Kam <shellzie@xxxxxxxxxxxxxxxxxxx>
• Subject: RE: .csv file
• From: Bill Hibbard <billh@xxxxxxxxxxxxx>
• Date: Tue, 8 Jul 2003 05:50:35 -0500 (CDT)

Hi Michelle,

> The visad spreadsheet was able to load in my csv file that had 7 input fields
> when I modified the header to what you suggested. However, I am trying to
> produce a 3-D glyph plot in which 3 fields are mapped to 3 parameters such as
> the x, y, and z axis, and 3 other fields mapped to 3 additional parameters
> local to that (x, y, z) point.
>
> However, when I load in my file with 7 input fields and create the mappings
> for a glyph plot, I only see about 3 small points on different faces of the
> cube rather than many points scattered throughout. Do you think the scarce
> number of plots could be from the values I gave each input field in my .csv
> file (some possibly too small) or could it be from the function I set up in
> the header?:
> (index) -> (GPA, Distance, Phone, Shoesize, Year, Xoffice, Yoffice,
> Firstname(Text), Lastname(Text)).

It is perfectly OK to have dependent variables mapped to
x, y, z, etc (anything but Animation or SelectValue, which
must be mapped from independent variables in 1-D domains).

If you want glyph plots, you'd do that with ScalarMaps to
Shape, which requires some code to build VisADGeometryArrays
and pass them to the setShapes() method of the ShapeControl
(see Test46.java and Test47.java in visad/examples). I don't
know why your points are all on the faces of your box - it may
just be the nature of your data - but its not because of
using dependent variables.

> I'm not exactly sure why these input fields like GPA and distance should be
> dependent variables and if they are going to be dependent variables, are you
> arbitrarily assigning the index to it?

Think of it this way, using a MathType of:

  ((GPA, Distance, Phone, Shoesize, Year, Xoffice, Yoffice) ->
   (Firstname(Text), Lastname(Text)))

says that name is a unique function of (GPA, Distance, Phone,
Shoesize, Year, Xoffice, Yoffice), which isn't necessarily so.
If everyone has a private office, then perhaps all the other
variables are unique functions of (Xoffice, Yoffice), in which
case you'd need an Irregular2DSet domain sampling for office
locations. But unless you're trying to visualize how shoesize
and GPA can be smoothly interpolated between offices (does GPA
drop off and shoesize increase in the executive suites?), you
don't need these to be independent variables.

Reminds me of a t-shirt I saw. It had a big C++ on it, and under
that in small letters it said "My boss's grade point average".

Good luck,
Bill

• References:
  • RE: .csv file
    • From: Michelle Kam