[vtkusers] data visualisation help

mushy2 salim mushy3 at hotmail.com
Mon Sep 25 14:41:59 EDT 2000

Hi vtkusers,

I have a datafile of eight columns, each column has about 300 rows (see 
attached datafile), from this datafile two columns need taken into an array 
(the two columns that are picked are always the same two columns) and the 
data in these two columns which are the x and y co-ordinates are then used 
to draw regions onto an applet.

All this has to be done in colour and and using java.

The size of a particular region depends on the size of its neighbours, if a 
particular region is very close to another region then the region will be 
small, if a region is far away from a region the region will be large; the 
size of every region is dependant on the size of its neighbours.

The colour of these regions come from three other columns in the datafile.  
The colours or the regions vary in intensity and colour

I have attached a datafile for you to look.  In the datafile there are eight 
(8) columns.

Column 1 and column 3 are used to draw the regions
Cloumn 1 = x co-ordinates and column 3 = y co-ordinates,

I have to use the data in these columns to draw regions, the data has to be 
interpretd in such a way that that the co-ordinates are representitive of 
the unique size of each region and as a whole all the unique regions fit 
into a square rectangle on an applet all this done propotionatly and 
according to the x and y co-ordinates of each unique region.

Every row of data in the datafile represents a unique region in the 

Columns 5, 6 and 7 are used to determine the colour of each region e.g.

       x               y               z
0.770036E-08   0.000000E+00   0.869663E-08

     v	           Mx              My
0.516719E-08   0.678963E+00   0.458836E-01

      Mz            Ms
-0.732737E+00   0.360000E+06

The data in the datafile is not like this, in the datafile the numbers are 
all in one row.  Every row in the datafile represents a dot in the scatter 
diagram.  The values Mx, My and Mz need to be used to derive a colour, to 
colour the squares of the mesh around the dot that the x and z co-ordinates 
of that row represents.   The vales in MX, My and Mz are not rgb or 
Hexadecimal colour values, but need to interpreted in such as a way that 
they represent colour values ( a technique known as value to colour 
mapping).  The column Ms is a non entity is has nothing to do with what I am 
trying to do, please ignore it.

I have an example of what a diagram should be like, and an example datafile 
for you to see the type of data I will be using, but I cannot send these via 
vtk so if you would like to see examples or have any queries, please email 
me at my hotmail address:

mushy3 at hotmail.com

Please could you help me with this, any source code, appropriate websites or 
personal help and supervision would be greatly appreiciated.

Thankyou for your help


Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com.

Share information about yourself, create your own public profile at 

More information about the vtkusers mailing list