[R] 3D scatter, groups, RdbiPgSQL...

[Tomas Lanczos]

hello,

I wish to create some 3d scatter diagrams visualising different grouped 
data set by a given field in the database. I tried the scatterplot3d 
package, as well as the plot3d and scatter3d functions (both within the 
rgl resp. Rcmdr package). My first question is, whether is it possibe to 
group data in the scatterplot3d and plot3d, because I did not succeed to 
use the groups = ... function.

The scatter3d behaves a bit wierdly with the groups function: it works 
well with data imported from a CSV file, but when I tried to apply it to 
a data imported from a PostgreSQL database (using the Rdbi and RdbiPgSQL 
packages) it gives me this error message:

ERROR:
   groups variable must be a factor.

To be more clear here is a command I used with the scatter3d (exactly 
the same for the both datasets):

scatter3d(br_scatter$cl, br_scatter$br, br_scatter$hco3, fit="linear", 
residuals=TRUE, bg="white", axis.scales=TRUE, grid=TRUE, 
ellipsoid=FALSE, xlab="cl", ylab="br", zlab="hco3", groups = 
br_scatter$stratigraphy)

the dataset I used is here (the same is the data imported from the CSV 
file and from a PostgreSQL table) looks like this (a part of it):

     stratigraphy           br        hco3          cl
1         sarmat 0.2327793352  507.006513  262.781114
2         sarmat 0.3741990388 1021.788317  214.254486
3          baden 0.3354024830 1268.847582  253.639356
4         sarmat 0.0938626352   46.514244   38.995620
5         sarmat 0.1163896676   18.300686   72.984568
6         sarmat 0.2090008010   77.777917  131.989947
7         sarmat 0.2815879055   53.802018  146.804052
8          panon 0.0450540649   81.590560  274.980467
9          baden 0.5619243092   61.752316  275.978980
10        karpat 0.4655586704   16.019351  179.537807
11    mezozoikum 0.6244993993  133.442504  152.986938
12         panon 0.1539347217  132.679975   65.994974
13        sarmat 0.0375450541   19.825743   24.996686
14        sarmat 0.0375450541   20.588272   26.280086
15         baden 0.0463055667   19.063215   26.494456
16         baden 0.1864737685   40.414016   93.992841
17        sarmat 0.9236083300   90.740903  597.954458
18         panon 0.8022126552   57.189645  499.961921
19         panon 0.4830796956   68.627574  280.001241
20         panon 0.1163896676   73.202745   53.995887

So why the exactly same "stratigraphy" field is a factor in the dataset 
imported from a CSV file and why is not a factor in the dataset imported 
from a PostgreSQL table

Many thanks in advance

Tomas