question about grouping in report template/ intelligent reporting in Open Lab CDS 2.5


I have a question about grouping in the report template/intelligent reporting in Open Lab CDS 2.5. (what is the difference?)

I am currently working on grouping three different injections of the same sample. The grouping parameters i have currently set to this: =IF(Compound_Name = "" , round(Peak_RetentionTime,2)   , Compound_Name )
This works perfectly for my named peaks, however when an unknown has a retention time of 0.01 more or less in one of the injections, they are obviously not grouped. How can i change my formula to include RT +/- 0.01

  • Hi, I'm interested to find out more. What does the report looks like if you remove the IF statement you are using for the grouping parameters? I'm not sure that the IF statement you are using is doing what you think it is. Did you create the table from scratch or is it from an Agilent report?


  • Hi

    If i remove the IF statement and put nothing in it's place there is obviously no grouping... Well there is, but the entire table is 1 group. (as seen by the average on the end)

    If i group on compound name, i only get the named compounds grouped seperately, and all the unknowns together

    If i only filter on retention time (rounded to 2 decimals), i have the same problem as before, but also with my known compounds. There cannot be a 0,01 difference in RT. 

    Therefore, the IF statement makes sure that when i have a compound name, it groups on compound name. If there is no compound name, it groups on RT.
    I could make my RT rounded to 1 decimal, but that raises other issues.

    1) 2 peaks cannot fall too close to each other, or they would be grouped. although since evere 0,1 minute is 6 seconds, this issue might not occur...
    2) if RT on a peak is x,54 in one injection and x,55 in another, they would still not be grouped. This might also not occur, but I would still prefer a foolproof solution.  

    As to answer

    The table is built from scratch. I have it in a composite group that filters on sample type and repeats on sample name like this:

    This way all 3 injections of the same sample are in the same table. However since every known and unknown peak needs to be averaged out, i thought the grouping would be nice.

    the table right now is just sample name - compound name - retention time - RRT (calculated with a variable of the main compound, made in an invisible table) - RRF (IF statement to make it 1,04 for 1 specific peak, else 1,00) - peak area 

    Hope this is enough info Slight smile

    kind regards

  • HI

    I'm not sure what you want to do is actually possible.  Wouldn't it be easier to include the peaks in the Compound Identification table and simply group on Compound_Name?


  • Hi
    We never include unknown peaks in our compound identification table, this would also not be doable for most of our systems, as there can be a ton of unknown peaks.

  • Thanks for the thorough explanation! I have given it alot of thought but unfortunately, i too am at a loss as to how to achieve a group from 3 different injections (of the same sample) using a  RT +/- 0.01 criteria.

    Hopefully someone else can help.


  • Hi

    Are you trying to group the unknown peaks by retention time together, using retention time (I think that's what I see).

    I would use a custom calculation to create a nominal retention time (with however many decimal places you need) for each peak and use this in your grouping.

    Would that work?


  • Hi
    I have no knowledge of custom calculations since i have never used them. So i would not know...


  • Hi, How would i do this?


  • A possible approach is to create a separate table for the unknown peaks by selecting the Unknown Peaks checkbox on the Peaks and Repeating tab, and then use 2 filters on the Filters tab to only show peaks with a +/- 0.01 retention variation to the expected. eg. with an expected rt of 15.38mins the filters would be >=15.37 and <=15.39. You would need to create the unknown peaks table for each of the 3 expected unknowns to be able to adjust the filters according to the expected rt.  This may not be the solution you are looking for but its worth considering as it would report out the average of each of the unknowns across the 3 replicate injections. For Grouping, i used a Group Repeat using Injection Sample Label whereby all reps of the same sample were assigned a unique sample label in the Injection List. 


  • Hi

    How to...

    Open the custom calculation editor from the Processing tab in the ribbon in Data Analysis

    Create a new custom calculation file and add a formula like this one (in this case, I've rounded to 1 decimal place to get consistency between all of the samples)

    Save the custom calculation file and add it to the processing method.  Reprocess and you should see an extra column in the Results table

    You can then use the custom calculation in the grouping in your results table.  The grouping in the report then need to be

     =IF(Compound_Name = "",CCR((Compound_CustomCalculationResults),"RoundedRT"), Compound_Name)

    The CCR part comes from the Compound fields

     I've done this with all of the files in an example result set. 

    Hope that makes sense.


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