Relative quantitation by AnalyzerPro and PyMS. Shown is a comparison of raw areas calculated by AnalyzerPro (x-axis) and PyMS (y-axis) for the data and segment depicted in Figure 3, including signal peaks correctly identified by both programs. The segment chosen for this analysis involves largely well-resolved peaks, and therefore provides a good test of relative quantitation without interference with potential errors originating from deconvolution. For each program its own internal algorithm was used to calculate peak boundaries and total peal areas. A good linear relationship in raw areas reported by two software packages was observed. The correlation coefficient for the data shown is 0.998.