# [Paraview] csv to geometry (was: paraview novice attempts 1st viz)

Moreland, Kenneth kmorel at sandia.gov
Wed Oct 3 18:33:08 EDT 2007

```You are not the first person to ask about this.  I was going to bring up
to the development team possible ways of deriving geometric data from
table/csv data.  My thought was to have a simple filter that allowed the
user to identify columns in a table and then produce a poly data
containing the points.  From there you could apply other filters (such
as Delaunay triangulation) to construct a topology.

Do you (or anyone else) have an opinion on how to interpret tables as
geometry?

-Ken

________________________________

From: fredrikaustin [mailto:fredrikaustin at yahoo.com]
Sent: Wednesday, October 03, 2007 10:15 AM
To: Moreland, Kenneth; paraview at paraview.org
Subject: RE: [Paraview] paraview novice attempts 1st viz

Of course I know paraview cannot interpret the data; perhaps I should
have said "I was looking for a way to tell paraview that I have three
columns of data, and that they correspond to points in x,y,z space
respectively.  Please plot the data".  This is a simple enough request,
provides all the information necessary, but I could not find any UI that
seemed designed for this simple purpose.

If there is not a simple way to plot such csv 3d data (as points in
space, as a surface, etc), I would think there should be.  It seems a
lot of data would start in this very straight-forward format.

-thomas blom

"Moreland, Kenneth" <kmorel at sandia.gov> wrote:

Sorry Thomas, but you are asking for the impossible.  You cannot expect
ParaView to magically apply semantic meaning to the columns of your data
and generate a topology that is not nonsense (at least, not without a
lot of help).  You have asked ParaView to read in a table (a csv holds a
table of data, no more, no less) and that is exactly what ParaView has
done.  You can view the data in a spreadsheet-type view and you can plot
the columns of data.

You should use a data format that gives the topological nature of your
data.  If your data is arranged in a 2D grid, you can store the data in
a simple image format.  The simplest image format is just a 2D array
written out as binary data to a file (read in with the "Raw (binary)
Files" reader).  ParaView also reads in .png files and it's pretty easy
to extend it to read other image files.

You can also stuff your data into VTK Legacy File format.  This is a
simple file format that supports most of the types of data that VTK can
handle and is pretty easy to build by hand.  You can get information
about hat format from the VTK User's Guide or in the following link.

http://www.vtk.org/pdf/file-formats.pdf

-Ken

________________________________

From: paraview-bounces+kmorel=sandia.gov at paraview.org
[mailto:paraview-bounces+kmorel=sandia.gov at paraview.org] On Behalf Of
fredrikaustin
Sent: Wednesday, October 03, 2007 7:14 AM
To: paraview at paraview.org
Subject: [Paraview] paraview novice attempts 1st viz

Hello all,

I'm having a difficult time viewing what must be the simplest data set
possible.  I have a csv file that includes 3 columns of numbers which
I'd like to view as 'elevation' type data: 1st two columns give x & y
coord (regular, though step-size for x and y are different), and 3rd
column gives a height (the data is actually error vs. 2 different
params).   I can open the file, and  see that it has read the columns of
data correctly, but can't get a plot of this surface.

Seems this should be simple to view, but after blundering around the
interface for too long, it is not as obvious as one would hope.

Thanks,
Thomas Blom

________________________________

Don't let your dream ride pass you by. Make it a reality
<http://us.rd.yahoo.com/evt=51200/*http:/autos.yahoo.com/index.html;_ylc
=X3oDMTFibjNlcHF0BF9TAzk3MTA3MDc2BHNlYwNtYWlsdGFncwRzbGsDYXV0b3MtZHJlYW1
jYXI->  with Yahoo! Autos.

________________________________