I am trying to modify a TDMS file that was already created from a test and I am trying to use DIAdem to modify the TDMS. The problem is, when I modify the TDMS and save it through DIAdem, DIAdem adds properties that I do not want to be in the TDMS file. These properties are "displaytype", "monotony", and "novaluekey". How do I prevent DIAdem from adding these properties OR how do I remove these properties from the TDMS file?
I have a VI that processes the TDMS file and it can only have certain properties (it cannot have the DIAdem generated properties). I have attached two files that detail what I am talking about. The first one is the original one (originTDMS) and the second one "tdmsDIAdem" is the one I modified with DIAdem and has the unwanted properties highlighted in yellow.
Any help is appreciated.
DIAdem will always, add those properties. It is not possible to avoid this.
DIAdem adds those properties because they are used to speed up plotting of the channel data and they are expensive to be calculated. Minimum and maximum do also belong to the added properties.
So DIAdem tries to avoid having to calculate them every time they are needed.
What are editing with DIAdem?
- Channel Data
There's no way around DIAdem writing those "magic 4" channel properties, along with others-- that's a "feature" that results in the file that DIAdem writes subsequently loading faster the next time it's read into DIAdem. You should be able to remove those properties after the fact with LabVIEW, though I haven't tried that myself. What I did try was to use the "CreateDataFileHeaderAccess()" command in a DIAdem script to return a DataFileHeaderAccess object variable. This can delete properties, but it only seems to work with TDM files, not TDMS files. When TDMS files first released, there was no way to remove any information from the file, so I'm guessing the DataFileHeaderAccess object was hard-coded to not try to delete properties from a TDMS file. I recall that this TDMS file restriction was relaxed several years ago, so removing a property from the file should be an option with LabVIEW VIs, which could be run from a DIAdem script with the LVRuntime object.
Principal Technical Support Engineer