Newbie question

[UnspecifiedError]

Hello,

I am new to DIAdem, I have gone through the basics, hand-on etc. But I have not been able to make much progress with my problem.

I was wondering if anyone can give me some pointers on how to proceed.

I have TDMS files being generated every hour for 90days. Yes a test lasts for 90days and there are mutilple stations!

There are different groups within each file and each group has its on LabVIEW timestamp.

I need to automate generation of some reports done daily, weekly and monthly etc.

So here are my thoughts:

combine 23 files using copy \b <hour0> + <hour2> ... <hour23> day.tdms

Then reduce the files by only taking every nth sample to form day_reduced.tdms.

Now combine all day_reduced to form month.tdms

I am not a big fan of duplicating data but I dont have much time to try things, Is the above ok?

Please help/comment!!

Thanks in advance.

[Brad_Turpin · Accepted solution]

Hi Unspecified,

Concatenating the TDMS files outside of DIAdem is certainly one good option-- the DOS concatenation option is pretty darn fast, but as you say that duplicates data.  Another option would be to reduce load each data file into DIAdem and concatenate them in the Data Portal.

Is there any way you can send or post several of these data files so I can see directly what you're dealing with?

Brad Turpin

DIAdem Product Support Engineer

National Instruments

brad.turpin@ni.com

[UnspecifiedError]

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@Brad_Turpin wrote:

Concatenating the TDMS files outside of DIAdem is certainly one good option-- the DOS concatenation option is pretty darn fast, but as you say that duplicates data.  Another option would be to reduce load each data file into DIAdem and concatenate them in the Data Portal.

Is there any way you can send or post several of these data files so I can see directly what you're dealing with?

---

Thanks for the reply. I think speed is very important and if you think DOS merge is the fastest, DOS merge it is.

I have managed to sort the other problems like remove invalid data, convert time stamp etc. using the following function (my vb is a bit rusty, I know some of it is cringe worthy) it does the job!

Sub DoPreparations(sTimeChannel,iGroupIndex)
    Dim Channel, UTC_Offset, LV_DD_Offset, sChnNoStr, sChnStr, j
    UTC_Offset = 8*(3600) ' secs from GMT to measurement location
    LV_DD_Offset = 60084288000 ' secs from 0 AD to 1904 AD
    Set Channel = Group.Channels(sTimeChannel)
    ChanStr = Channel.GetReference(eRefTypeIndexName)
    Group.Activate
    sChnStr = "Ch(""[" & Str(iGroupIndex) & "]/" & sTimeChannel &""")=1/(1/Ch(""[" & Str(iGroupIndex)&"]/" & sTimeChannel &"""))"
    Call Calculate(sChnStr,NULL,NULL,"")
    sChnNoStr = Str(cnoxget(iGroupIndex,1))&"," & Str(cnoxget(iGroupIndex,3)) & "-" & Str(cnoxget(iGroupIndex,GroupChnCount(iGroupIndex)))
    FOR j = 1 To Group.Channels.Count
      IF Channel.Properties("length").Value = Group.Channels(j).Properties("length").Value THEN
      ELSE
        Group.Channels(j).Properties("length").Value = Channel.Properties("length").Value
      END IF
    NEXT 'j
    IF Channel.Properties("novaluekey").Value = "Yes" THEN
      Call ChnNovHandle(Channel,sChnNoStr,"Delete","X",True,False)
    End IF
    ChnFormat(ChanStr) = "Time"
    Call ChnLinScale(Channel, Channel, 1, LV_DD_Offset-UTC_Offset)
    
End Sub 

I then use

Call DataFileLoadRed("<file>","TDMS","","IntervalWidth",%d,1, NULL, NULL)

to decimate the file. Job Done.

I am impressed by the speed of it all.... Customer impressed! Kudos to the DIAdem team.