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19.1.10.9 Peak Analyzer, Find Peaks Page


This page is available in the Peak Analyzer only when neighter Create Baseline nor Subtract Baseline is selected for Goal in the Start page. It helps you to find the peaks in the spectrum data.

Dialog Box Controls

Current Number of Peaks

This is read-only. It shows the number of peaks that have been found.

Enable Auto Find

Use this to specify whether you want the Peak Analyzer to find the peaks automatically. When this check box is selected, the Add, Modify/Del, Clear All and Load buttons are disabled.

Find

This button makes Origin find peaks using the current settings in the Find Peaks Settings and Peak Filtering groups.

Add

This button is enabled only when the Auto Find check box is not selected. When this button is clicked, you are allowed to add peaks manually, by double-clicking on the preview graph. The coordinates of mouse click will be shown in Data Display Window for better selection.

Modify/Del

This button is enabled only when the Auto Find check box is not selected. When this button is clicked, you are allowed to modify or delete the peaks on the preview graph. The coordinates of selected anchor points will be shown in Data Display Window for better identification.

Clear All

This button is enabled only when the Auto Find check box is not selected. When this button is clicked, all existing peaks are removed.

Save

Click this button to save the current peak info to a .dat file.

Load

This button is enabled only when the Auto Find check box is not selected. When this button is clicked, you can load peak info from a file.

Peaks Info

When this button is clicked, the Peak Info dialog opens, showing you the information (centers and heights) of the peaks. You can sort peaks, add or delete a peak, and edit the peak info in the dialog, if the Auto Find check box is not selected. You can also copy the peak info or paste a specific center/height value for a peak by the Copy/Paste button.

Peak Info Dialog Button Group

  • Sort Center Ascending button Sort Anchor Points Button.png
    Sort peak anchor points in ascending order by peak centers.
  • Copy button Copy Anchor Points Button.png
    Copy selected peak anchor points in anchor points list.
  • Paste button Paste Anchor Points Button.png
    Paste copied peak anchor points in clipboard into the peak anchor points list in Peak Info dialog.
  • Add button Add Anchor Points Button.png
    Add a peak anchor point to the end of peak anchor points list.
  • Delete button Delete Anchor Points Button.png
    Remove selected peak anchor point(s) in anchor points list.
Snap to Spectrum

This checkbox is enable only when Enable Auto Find is unchecked. Use this checkbox to specify whether you want the peak center anchor points to be snapped to the spectrum data. If this is selected, the peak center anchor points will be pulled onto the spectrum as you add or move them.

The Peak Finding Settings Group

Show 2nd Derivative

Use this check box to show or hide the panel that plots the second derivative of the spectrum data and its smoothed data(in red color) in the preview graph. The second derivative can be helpful in locating peaks (including hidden peaks) in the spectrum.

Smooth Window Size

Savitzky-Golay smoothing can be performed on the spectrum data before the peak finding. If you want to perform the smoothing, enter the desired window size (a positive integer) in the moving window for the Savitzky-Golay smoothing. Otherwise, enter 0 in this text box. There is an Auto check box to the right. When it is selected, the smooth points will be determined by the Peak Analyzer automatically. If you want to specify the smooth points, uncheck this box.

Method

Use this drop-down list to select the method to find the peaks.

  • Local Maximum
    Use the Local Maximum method to find the peaks in the spectrum.
  • Window Search
    Use the Window Search method to find the peaks in the spectrum.
  • 1st Derivative
    Use the first derivative method to find the peaks in the spectrum.
  • 2nd Derivative (Search Hidden Peaks)(OriginPro only)
    Use the 2nd Derivative method to find the peaks in the spectrum. This method is capable of detecting hidden peaks in the data.
  • Residual after 1st Derivative (Search Hidden Peaks)(OriginPro only)
    Use the Residual after 1st Derivative method to find the peaks in the spectrum. This method is capable of detecting hidden peaks in the data.
Direction

Use this drop-down list to specify whether or not to find peaks with a specified direction only.

  • Positive
    Find positive peaks only.
  • Negative
    Find negative peaks only.
  • Both
    Find both positive and negative peaks.
Local Points

This is available only when Local Maximum is selected in the Method drop-down list. It specifies the number of points in the local area, which will be used for finding the peaks with the Local Maximum method.

Size Option

This is available only when Window Search is selected in the Method drop-down list. This drop-down list specifies how the Height and Width values (see below) are interpreted.

  • Raw Size
    The values will be interpreted as raw sizes.
  • Percent of Raw Data
    The values will be interpreted as the percentages with respect to the total width or maximum height of the spectrum data.
Height

This is available only when Window Search is selected in the Method drop-down list. It specifies the height of the rectangle, which is used to find the peaks. There is an Auto check box to the right. If it is selected, the Peak Analyzer will determine the value automatically. Therefore, if you want to edit the value, please uncheck this check box.

Width

This is available only when Window Search is selected in the Method drop-down list. It specifies the width of the rectangle, which is used to find the peaks. There is an Auto check box to the right. If it is selected, the Peak Analyzer will determine the value automatically. Therefore, if you want to edit the value, please uncheck this check box.

Smooth Derivative

This is available only when 1st Derivative(None and SG only), 2nd Derivative (Search Hidden Peaks) or Residual after 1st Derivative (Search Hidden Peaks) (None and SG only) is selected in the Method drop-down list. Specifies the method to smooth the derivative of spectrum data.

Method
Specifies the smoothing method.
  • None
    Do not use any smoothing method.
  • FFT
    Specifies the FFT Filter method to smooth derivative.
  • ADJ
    Specifies the Adjacent Averaging method to smooth derivative.
  • SG
    Specifies the Savitsky-Golay method to get smooth derivative.
  • Quadratic SG
    Specifies the Quadratic Savitsky-Golay method to smooth derivative.
Cut Off Frequence
It is available only when the Smooth Derivative drop-down list selected to FFT. It specifies the cutoff frequency.
Points of Window
It is available only when the Smooth Derivative drop-down list selected to ADJ, SG and Quadratic SG. The greater this value, the greater the degree of smoothing. A value of zero for this parameter will leave the data unsmoothed.
Polynominal Order
It is available when the Smooth Derivative drop-down list selected to ADJ and Quadratic SG. It specifies the polynomial order.

The Peak Filtering Group

Method

Use this drop-down list to specify whether you want to limit the number of found peaks or the height of the peaks.

  • None
    Select this option if you do not want to limit the number of found peaks nor the heights of the peaks.
  • By Height
    When you select this option and specify a threshold height with the Threshold Height(%) text box, only the peaks whose heights are not less than the threshold height will be found when you click the Find button. There is an Auto check box to the right. When it is selected, the smooth points will be determined by the Peak Analyzer automatically. If you want to specify the height, make sure the clear this check box.
  • By Number
    If you select this option and enter a value in the Number of Peaks text box, you can limit the number of peaks that will be found after you click the Find button. There is an Auto check box to the right. When it is selected, the smooth points will be determined by the Peak Analyzer automatically. If you want to specify the number of peaks, make sure the clear this check box.
Threshold Height(%)

This text box is available only when Height is selected in the Filter Method drop-down list. You can use it to specify the minimum height of the found peaks. It is a percent of a reference value, which is defined as follows:

First, get the maximum value and the minimum value of the spectrum (if a baseline has been subtracted from it, use the spectrum after subtraction). Then compare the absolute values of the maximum value and the minimum value. The greater one will be regarded as the reference value of the Threshold Height.

Number of Peaks

This text box is available only when Number is selected in the Filter Method drop-down list. You can use it to specify the maximum number of the found peaks.

The Labels and Markers Group

Show Center Label

Use this check box to specify whether or not to show a label for each peak center.

Center Label

Select the type of center labels.

  • X of Peaks
    Use the X coordinates of the peak centers as center labels.
  • Y of Peaks
    Use the Y coordinates of the peak centers as center labels.
  • Indices
    Use the indices of the peaks as center labels.
  • (X,Y) of Peaks
    Use the X and Y coordinates of the peak centers as center labels.
Rotate Center Label

Use this check box to specify whether or not to rotate the center labels.

The Peak Fitting Bounds Group

This group is available only when Goal is set to Fit Peaks.

Preset Bounds by

Use this drop-down list to specify whether and how you want to set boundaries to the found peaks while fitting.

  • None
    Select this option if you do not want to preset the boundaries of the peak center, widths nor heights of found peaks.
  • By Difference
    Specify boundaries by difference between center and upper/lower bound. When you select this option and specify values of Center, Width and/or Height/Area, peaks fitting will be limited to the center, width and/or height boundaries you set.
  • By Percentage
    Specify boundaries by the percentage of the difference between center and upper/lower bound. When you select this option and specify the percentage values of Center(%), Width(%) or Height/Area(%), peaks fitting will be limited to the center, width and/or height boundaries you set.
Center This option is available only when By Difference is selected for Preset Bounds by. Check the checkbox and specify the upper and lower bounds for peak center.
Width This option is available only when By Difference is selected for Preset Bounds by. Check the checkbox and specify the the upper and lower bounds for peak width.
Height(Area) This option is available only when By Difference is selected for Preset Bounds by. Check the checkbox and specify the upper and lower bounds of peak height or peak area.
Center(%) This option is available only when By Percentage is selected for Preset Bounds by. Check the checkbox and specify the upper and lower bounds in percentage of peak center.
Width(%) This option is available only when By Percentage is selected for Preset Bounds by. Check the checkbox and specify the upper and lower bounds in percentage of peak width.
Height(Area)(%) This option is available only when By Percentage is selected for Preset Bounds by. Check the checkbox and specify the upper and lower bounds in percentage of peak height or peak area.
 

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