I am trying to create a custom calculation to determine if the peak area of an unidentified peak is = the peak area of a compound in a standard run (reporting limit criteria).

Question

As stated in the title, I'd like to determine if the peak area of an unidentified peak is >= the peak area of the reporting limit standard. I'm using the CCs below and it will only report the results for the identified compound. How do I get this calculation to be reported for all integrated/unidentified peaks?

1. Determine what is the last checked reporting limit standard was. (LastCheckRLSTD)

If(CurrentSample.Sample_Type<>15, CurrentSequence.AllSamples.Where(function(y) y.Sample_OrderNumber<CurrentSample.Sample_OrderNumber).Where(function(y) y.Sample_Type=15).Select(function(y) y.Sample_Name).Last, "N/A")

2. Index the peak area of the compound peak in the reporting limit standard. (LastCheckRLSTDPeakArea)

CurrentSequence.AllIdentifiedPeaks.Where(function(y) y.Injection.Sample.Sample_OrderNumber<CurrentSample.Sample_OrderNumber).Where(function(y) y.Injection.Sample.Sample_Name=LastCheckRLSTD).Where(function(y) y.Compound_Name=CurrentPeakOrGroup.Compound_Name).Select(function(y) y.Peak_Area).Last

3. Determine if the peak area of an unidentified peak is greater than the peak area of the reporting limit standard.

If(Compound_Name="", If(Peak_Area > LastCheckRLSTDPeakArea, "Met", "Unmet"), "N/A")

Any help is greatly appreciated.

martin.adams · Accepted Answer

Hello, 
 
 Are you trying to compare the unknowns to a specific named compound area in the Spike samples? You are combining AllIdentifiedPeaks with " Where ( function (y) y. Compound_Name = CurrentPeakOrGroup. Compound_Name" if you are doing this calculation at peak scope then you will not get any results for unknowns. Even if you had done allpeaks it would have compared all the unknowns to the last one in the chromatogram. 
 
 Try this at a peak or group scope and type of string. You will need to change the compound name to the name of the compound you test the unknowns against. 
 If(Compound_Name.Length > 0, "N/A", If(Peak_Area > CurrentSequence.AllIdentifiedPeaks.Where(function (x) x.Injection.Sample.Sample_Type = 4).Where(function (x) x.Compound_Name = "Peak C").Where(function(y) y.Injection.Sample.Sample_OrderNumber<CurrentSample.Sample_OrderNumber).OrderBy(function(x) x.Injection.CreationTime).Select(function(x) x.Peak_Area).Last,"Met","UnMet")) 
 Marty Adams

martin.adams · Answer

Hello, 
 
 Sorry, I was not more precise in the first reply. You need to change "Peak C" to the name of the peak in your Spike samples that you want to compare against. You can use like and wildcards if you do not want to type the entire name. You could also do .ToUpper if you wanted to make it case insensitive, but the example CC is the simplest format. For the example the name must match exactly the compound name in the method. 
 
 Marty Adams 
 
 If(Compound_Name.Length > 0, "N/A", If(Peak_Area > CurrentSequence.AllIdentifiedPeaks.Where(function (x) x.Injection.Sample.Sample_Type = 4).Where(function (x) x.Compound_Name = "Your Peak Name Here").Where(function(y) y.Injection.Sample.Sample_OrderNumber<CurrentSample.Sample_OrderNumber).OrderBy(function(x) x.Injection.CreationTime).Select(function(x) x.Peak_Area).Last,"Met","UnMet"))

martin.adams · Answer

Yes, you will want to start with AllInjections and you can also remove the compound name where clause. I would also change the scope to injection. 
 
 Marty Adams 
 
 CurrentSequence. AllInjections . Where ( function (x) x. Sample . Sample_Type = 5 ). Where ( function (y) y. Sample . Sample_OrderNumber < CurrentSample. Sample_OrderNumber ).OrderBy( function (x) x. CreationTime ). Select ( function (x) x. Sample . Sample_Amount ). Last

I am trying to create a custom calculation to determine if the peak area of an unidentified peak is >= the peak area of a compound in a standard run (reporting limit criteria).

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