FitSinglePeak: Performs a peak fit.

In pasturm/TofDaqR: R Interface to the TOFWERK TofDaq API

Performs a peak fit.

Description

FitSinglePeak performs a peak fit. Gaussian, Lorentzian and Pseudo-Voigt peak shapes are supported.

Usage

FitSinglePeak(
  yVals,
  xVals,
  peakType = 0L,
  blOffset = 0,
  blSlope = 0,
  amplitude = 0,
  fwhmLo = 0,
  fwhmHi = 0,
  peakPos = 0,
  mu = 0
)

Arguments

yVals	y axis data.
xVals	x axis data.
peakType	peak model to use.
blOffset	Initial value of baseline offset at first data point.
blSlope	Initial value of slope of baseline.
amplitude	Initial value of peak amplitude.
fwhmLo	Initial value of left peak width (full width at half maximum).
fwhmHi	Initial value of right peak width (full width at half maximum).
peakPos	Initial value of peak position.
mu	Initial value of Gaussian/Lorentzian contribution.

Details

Peak parameters are optimized using a Levenberg-Marquardt algorithm as implemented by the library lmfit. The following peak types are available:

peak type index	peak function	symmetric	baseline
-1	Gaussian through highest point and its neighbours	yes	no
0	Gaussian	yes	no
1	Lorentzian	yes	no
2	Pseudo-Voigt	yes	no
3	Gaussian	yes	yes
4	Lorentzian	yes	yes
5	Pseudo-Voigt	yes	yes
6	Gaussian	no	no
7	Lorentzian	no	no
8	Pseudo-Voigt	no	no
9	Gaussian	no	yes
10	Lorentzian	no	yes
11	Pseudo-Voigt	no	yes

The function for peakType = -1 is not an actual peak fit but rather the Gaussian function (symmetric, no baseline) defined by the maximum intensity point and its neighbors. It is used to automatically generate guess values for position, width and amplitude if all peak parameters are set to 0.

Value

List with peak parameters.

See Also

Other Peak fitting functions: EvalMultiPeak(), EvalSinglePeak(), FitSinglePeak2(), MultiPeakFit()

pasturm/TofDaqR documentation built on March 29, 2024, 12:10 a.m.