4.4.7.2 Peak Fitting with Preset Peak Parameters


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Summary

In some cases, you may want to perform peak fitting with preset peak parameters. For example, you may have many datasets with fixed numbers of peaks and the centers of these peaks do not vary from dataset to dataset. What you are interested in is mainly other parameters of the peaks, for example, heights. Using the theme feature of the Peak Analyzer, you may carry out peak fitting with fixed peak parameters easily.

Minimum Origin Version Required: OriginPro 2016 SR0

What You Will Learn

  1. How to save Peak Analyzer settings in a theme and reuse them
  2. How to fix peak parameters

Steps

Save a theme with peak positions and peak parameters

  1. Start a new worksheet and import the file <Origin Program Folder>\Samples\Spectroscopy\HiddenPeaks.dat.
  2. Highlight the second column and select Analysis: Peaks and Baseline: Peak Analyzer from the Origin menu to open the Peak Analyzer.
    Peak Fitting with Preset Peak Parameters 01.png
  3. On the first page, select the Fit Peaks radio button in the Goal group. Click Next to go to the Baseline Mode page.
    Peak Fitting with Preset Peak Parameters 02.png
  4. In the Baseline Mode page, select None (Y=0) with the Baseline Mode drop-down list. Click Next to go to the Find Peaks page.
    Peak Fitting 01.png
  5. In the Find Peaks page:
    1. Clear the Enable Auto Find check box, because we want to find the peaks manually. Click the Peaks Info button to open the Peak Info dialog.
      Peak Fitting with Preset Peak Parameters 04.png
    2. In the Peak Info dialog, click the Add button seven times to add 7 peaks. Enter the peak centers and heights as follows:
      Peak Fitting with Preset Peak Parameters 05.png
      Click OK to return to the Peak Analyzer.
    3. Click Next to go to the Fit Peaks page.
  6. In the Fit Peaks page:
    1. Click Fit Control to open the Peak Fit Parameters dialog.
    2. In the Peak Fit Parameters dialog, click the Fix or release all peak centers button. Then click the Fit Until Converge button. When the fitting is done, click OK to return to the Peak Analyzer dialog (see this important note about Fit until converged).
      Peak Fitting with Preset Peak Parameters 06.png
    3. Click the right-sided triangle button to the right of Dialog Theme in the upper panel. Select Save As from the short-cut menu. The Theme Save as dialog opens.
    4. In the Theme Save as dialog, enter MyFitting after Theme Name. Clear and select the check boxes as the screenshot below:
      Peak analysis theme 1.png
      Click OK to save the theme. This should bring you back to the Peak Analyzer dialog.
    5. Click the Finish button in the Peak Analyzer to complete the analysis.

Reuse the theme

  1. Start another new workbook and import the file <Origin Program Folder>\Samples\Spectroscopy\HiddenPeaks.dat.
  2. Highlight the second column
  3. Select Analysis: Peaks and Baseline: Peak Analyzer from the Origin menu to open the Peak Analyzer dialog.
  4. On the first page of the Peak Analyzer, click the right-sided triangle button to the right of Dialog Theme. From the short-cut menu, pick MyFitting.
    Peak Fitting with Preset Peak Parameters 08.png
  5. Click Next to check if the settings in every step are correct. Note that in the Find Peaks page, you can see the peak centers and heights are same as last time.
  6. When you reach the last page, click the Fit Control button to open the Peak Fit Parameters dialog. Make sure that all peak centers are fixed and the values are the same as last time. Click OK to return to the Peak Analyzer.
  7. Click Finish to complete the analysis. Check the results to see whether they are the same as the results we got last time.