OriginPro 7 - Peak Fitting Module (PFM)

An indispensable tool for the analysis of multi-peak data sets

OriginPro 7 now includes the Peak Fitting Module. This tool offers a wizard-based interface to walk you through the steps of advanced peak analysis. The Peak Fitting Module offers the ability to automatically detect a baseline and peak locations, then fit over 100 peaks. The Peak Fitting Module contains an extensive set of built-in functions, providing you with the ultimate in flexibility when performing your least squares fitting and peak data set analysis. Individual peaks can even be assigned to use a specific function. You can also create your own user-defined functions with arbitrary baselines. The wizard-based interface allows you to save your curve fitting procedures to reuse later with a click of a button.

Work in chromatography, spectroscopy, engineering, pharmacology, and other fields frequently requires analysis of data sets exhibiting multiple peaks. Analysis of multi-peak data is particularly difficult when peaks overlap, or when data are "noisy." The PFM combines the tools needed for serious peak analysis -- data filtering, automatic and/or manual baseline and peak detection, built-in or user-defined curve fitting functions, highly accurate non-linear least squares curve fitting, and publication-quality output - with an intuitive and easy-to-use interface, to create a powerful and essential research tool.

The PFM is intuitive and easy to use.

The PFM is easy to use, owing to a completely redesigned wizard interface. The wizard guides you through the entire fitting process, from data selection to report generation and the saving of fitting procedures to toolbar buttons for repeat analyses.

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The left side of the wizard is a color-coded map that lists PFM logically ordered pages and presents an overview of the entire fitting sequence.

The center portion of the wizard features the page controls. Choose and pre-condition data, specify and subtract a baseline, specify peak locations automatically and/or manually, choose individual peak functions, and perform your fit.

The right side of the wizard graphically depicts your data. Zoom in on a portion of the plot, scroll right or left, view plots of residuals or the smoothed second derivative of your data (useful for finding hidden peaks), display individual peaks and confidence or prediction bands, and view, fix, or constrain parameter values. All of this can be done at the touch of a button.

The PFM wizard guides you through each step in the peak fitting procedure, from data input to publication-quality output.

The PFM wizard's logically ordered pages guide you through each step of the peak fitting process:

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• Import data from a variety of sources (ASCII, MS Excel, etc.).
• Specify a sub-range of the data.
• Filter or transform the data.
• Define and subtract a baseline by one of four methods.
• Specify built-in or user-defined functions for each peak.
• Automatically locate peaks by specifying a threshold height or number of peaks. Manually locate peaks by point-and-click.
• Graphically adjust peak parameter values.
• Display plots of residuals or second derivative (helpful in finding hidden peaks in data).
• Plot confidence and prediction bands. Display individual peaks.
• Save routines to a toolbar button.
• Create presentation quality reports for printing or export to EPS, TIF, BMP, JPG, PNG, PSD, AI, PDF, WMF, EMF, CGM, DXF.

The PFM is engineered to save you valuable time.

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Pages can be reviewed and the details of the fitting session changed. You can add or delete peaks manually, undo baseline subtractions or data filtering operations, adjust peak parameter values either graphically or by editing numerical fields, or choose curve-fitting functions peak-by-peak. Each adjustment can be made without the need to restart your entire fitting session.

Additionally, you may opt to use PFM's newly implemented automatic baseline and peak-detection algorithms to define a baseline or to find peak centers and heights. You can further expedite your analyses by initiating the fitting session with a custom file: specify the number of peaks, peak function(s), baseline function, initial parameter values, share or fix parameters, or specify constraints, pre-set the number of iterations to be performed, specify tolerance levels (delta chi-square), and select the format of your Peak Characterization Report.

Save your procedures to a toolbar button for repeat analyses.

Finally, the entire peak fitting process can be greatly streamlined by saving the details of your fitting session to a tool bar button.

When performing repeat analyses, extraneous pages and operations will be skipped. Pages for which identical actions will be performed - automatic detection of peaks above a threshold height, for instance - may be hidden as well, and the action will be automatically performed on your current data set. The PFM interface was designed to adapt to your particular peak fitting needs.