Example 14: RT/Average RT (... (Custom Calculation)
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Example 14: RT/Average RT (in standards)

  • Scope: Peak or group

  • Type: Double

  • Find a function for average in aggregate functions

  • Find a function to return a list of Matching peaks (AllMatchingPeaksOrGroups).

  • Choose the MatchOption. Since you want a ratio for all peaks, choose MatchOption.Closest. It’s better here to use the delta so that the ratio is not computed with a peak too far away.

  • Define the list of peaks where you want to search the matching peaks (CurrentSequence.AllPeaks).

Formula

Peak_RetentionTime/Average("Peak_RetentionTime", AllMatchingPeaksAndGroups(MatchOption.ClosestRT, 0.1, CurrentSequence.AllInjectionsOfType(SampleType.Calibration))) (evaluates all signals)

or

Peak_RetentionTime/Average("Peak_RetentionTime", AllMatchingPeaksAndGroups(MatchOption.ClosestRTOnSignal, 0.1, CurrentSequence.AllInjectionsOfType(SampleType.Calibration))) (evaluates only the same signal as for the current peak)