Option to disable point and cell renumbering

ParaView Support
1

Hi,

I’ve noticed that ParaView renumbers points and cells from imported data in such a way that they start from 0. So, for example, it shows cells 0 and 1 when my elements are originally named 1 and 2. This can be quite troublesome when exporting data together with IDs for further use. Thus, it would be great if you could add an option to disable this renumbering and use original numbers for imported data.

2

This cannot ba a global option, however when origin Id matter, the reader could provide the original ids as a field on the data. Which file format are you looking at @FEngineer ?

3

I’m using CalculiX results files (.frd) converted to .vtk. I also have input files for that solver and nodes are defined there in order using the following syntax:

*Node
      number, x_coordinate, y_coordinate, z_coordinate

But I don’t know if those could be used to create fields with proper names (starting from 1). It would be best to take the numbering from .frd if possible.

4

CalculiX results files (.frd) converted to .vtk.

Then ths issue is in your converter

5

All right, I’ll contact its provider. I thought that ParaView renumbers the nodes so that they always start from 0. Is there a workaround for that in ParaView ?

6

It doesn’t “renumber”, this is just how nodes are defined in your .vtk file.

7

I see. But I don’t know if and when this will be changed in the converter so it would be good to have an option to create a field with IDs starting from 1 if possible.

8

There is no reason to have such an option for all reader. Anyway, it is trivial to create using Calculator filter.

9

I tried using Generate Ids and then Calculator with PointIds+1 formula but it didn’t work. How should I do it ?

10

I tried using Generate Ids and then Calculator with PointIds+1 formula but it didn’t work.

Do you have an error to share ?

11

It’s working now, I probably selected PointIds instead of Result as Point Labels in Find Data.

12

@mwestphal I got the reply from the developer of this .frd to .vtk converter. He said that, according to VTK User’s Guide (19.3 VTK File Formats chapter), IDs have to start from 0 in vtk files. And indeed there’s such information in that document:

Indices are 0-offset. Thus the first point is point id 0.

Does it mean that converters to .vtk have to obey this rule (also for cells) and that’s why IDs in ParaView always start from 0 ?

13

As I stated earlier:

the reader could provide the original ids as a field on the data.

So you can add a point data containing the original Id.