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FindGraph performs nonlinear peak separation and analysis for spectroscopy, engineering, and chromatography.
Import data from a variety of sources (ASCII, MS Excel, etc.), filter or transform the data,
and run the wizard.
Peaks Fitting Wizard guides you through each step of the peak fitting process.
On first step specify a sub-range of the data. For some data sets, it is more efficient to fit several
subsets of your peaks rather than all at once.
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Specify and subtract a baseline.
FindGraph supports a constant baseline (offset), a line in fixed points, a cubic polynomial, or an exponential to fit peaks with a baseline function.
The initial baseline points can be set in several ways.
An automated FFT smoothing is applied to find all local minimum to define baseline.
You can interactively draw or edit this points with the mouse.
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In general, it is much better to fit with a baseline function than
to try to remove the baseline from the data and then fit.
However, you can use other FindGraph baseline modeling tools
to specify and subtract out the baseline before the fit.
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Specify peak locations automatically and/or manually
The initial values for the fit, i.e., the number, X placement, height, and semi-width
of the peaks can be set.
Up to 15 peaks are supported.
Automatically locate peaks by specifying a threshold width of peaks.
FindGraph initially places peaks by finding all local maximum
in a smoothed data stream.
Manually locate peaks by point-and-click with the mouse.
You can delete the current peak, insert a new peak or edit an old peak.
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It is possible to display the smoothed second derivative of your data.
It may be helpful in finding hidden peaks.
If you know that two or more peaks must be separated by a certain interval,
fit each peak near its initial X placement in semi-width interval only.
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Choose peak function, and perform your fit.
FindGraph can fit multiple overlapping peaks using one
of 20 basic peak fit types used in X-ray spectroscopy, engineering, and chromatography:
Gaussian, Lorentzian, Voigt, ExpGaussian, Asymmetric Gaussian, Inverse Polynomial, Edgeworth-Cramer, and more...
FindGraph will adjust the X placement, width, height, and symmetry to fit peaks.
Software provides automatic logging of multi-peaks fitting analysis including coefficients, standard error, residual graphs.
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Generate graphical as well as tabular results
for a wide range of peak characteristics.
The residuals plot is very handy in deciding
whether the fit is good or whether there may be additional peaks.
The baseline can be shown as well.
In the following result after a fit, the residuals are just noise indicating a good fit.
Read more about:
 Digitizing
Graphing
Curve fitting
Best-fit equation
Closed curves
Empirical models
Library
Analysis
Tools
Filters
Convolution
Periodic signals
Procrustes analysis
SSA forecasting
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