Area reject on individual chromatograms?

Question

Compound A elutes in each chromatogram and i want to report the peak areas in each chromatogram that are greater than the peak area of Compound A in each chromatogram. As the area of Compound A varies in each chromatogram i can't use the area reject in the processing method as this applies globally to all chromatograms. 
 Can you help find a way to do this? I am using OpenLab 2.3. 
 Regards

camelia · Accepted Answer

To update - i have found a way to report only peaks which are greater than Compound A on an individual chromatogram basis. This involved linking and processing the results set with the following CC to find the peak area of Compound A in each specific injection: 
 CurrentInjection. SignalByName ( Signal_Name ). PeakOrGroupByName ( "Compound A" ). Peak_Area . 
 and then calling this CC as the Value in the Filtering properties of a table using Peak_Area as Value and > as Operation. To get the CC into the Value field i selected Compound, Custom Calculation Results then the identifier that i gave the CC in the CC file. This table was repeated for each sample. 
 This was achieved by trial and error really but thought it worth sharing. If there is any other way of achieving this output without using a CC i would be keen to know. 
 Thanks

dwaelsve · Answer

you could have an invisible table, filtered to samples (sample type) and compound A. Then in the column for area, save the result as a variable with unique key value = sample name. In the samples table where you report you can then compare a peak against the variable that you just created, which will automatically be different for each sample. 
 let me know if i have to elaborate on it

martin.adams · Answer

Camelia, 
 
 The code to use in a filter expression to get a variable when not directly available( CDS 2.1 up to 2.4 and in C.01.10 Chemstation) is below. CDS 2.5 allows direct access to variable in the filters. The one limitation is that variables must be numeric values. 
 
 Marty Adams 
 
 Here is a simple example. 
 Define a variable (&ldquo;PeakNumber&rdquo;) saved as unique key value on Peak_ID. If you do not have an index you can leave that out. Note: This only works in C.01.10 Chemstation and CDS 2.1 and higher. 
 Then use is in a filter as following to show the 10 biggest peaks: 
 
 Code.DVL.GetValue(Peak_ID & &ldquo;PeakNumber&rdquo;) > 0 
 And 
 Code.DVL.GetValue(Peak_ID & &ldquo;PeakNumber&rdquo;) <= 10

Area reject on individual chromatograms?

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