Peak Search Algorithm
Our peak search program adopts a method that does not require any kind of prior processing such as smoothing and background subtraction.
The following are parameters of a peak:
x_{0} : peak position,
h : peak height,
FWHM : full width at half maximum.
The following 14 explain all the steps of the algorithm:

Computes the second derivative of the input xy plot data, by using a cubic polynomial that approximates the xy plot locally.

Obtain all the local minimum points of the second derivative with a negative yvalue.
Approximate the area between the xaxis and the graph of the second derivative (A in the following figure):
Figure 1 : Example of the second derivative of a 1dimensional Guaussianlike peak.

Using the following formula, estimate the peak height h at every local minimum point x_{0} ("peak height" means the "yvalue of the peaktop" minus "estimated background value"):
where x_{1} and x_{2} are the xcoordinates at which the second derivative equals zero (Figure 1).

If the above h is larger than the threshold determined from the input parameters,
a peak with the height h exists at x_{0}.
Estimate the FWHM using the following formula:
Eq. 1 and Eq. 2 are the equations any 1dimensional Gaussian function
satisfies.
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