ppick.RdFind local extrema in NMR spectra (peak picking)
ppick(X, ppm, fil_p = 3, fil_n = 5, type = "max")
| X | num matrix, NMR matrix with spectra in rows |
|---|---|
| ppm | num vec, chemical shift matching to X |
| fil_p, | SG filter order |
| fil_n | num, SG filter length (must be odd) |
| type | str, return local extrema: maxima ( |
List of data frames for each spectrum. Each data frame has four columns: index in X col/ppm, ppm value, signal intensity and local extrema type (+1 for local min, -1 for local max). Number of rows match to all local extrema found within a spectrum.
Function first smoothes the spectrum to reduce extrema related to noise fluctuations using a Savitzki-Golay (SG) filter. Local extrema are identified according to sign change of adjacent points.
Other NMR:
alignSegment(),
bline(),
excise1d(),
get.idx(),
lw(),
matspec(),
noise.est(),
normErectic(),
plotload(),
read1d_raw(),
read1d(),
specload(),
spec(),
stocsy1d_metabom8-class,
stocsy(),
storm()
data(covid) peaks=ppick(X, ppm) # Plotting first spectrum in reagion 3.0 to 3.15 ppm spec(X[1,], ppm, shift=c(4.2, 5.3)) points(speaks[[1]]$ppm, speaks[[1]]$Int, col=factor(speaks[[1]]$type))#> Error in points(speaks[[1]]$ppm, speaks[[1]]$Int, col = factor(speaks[[1]]$type)): object 'speaks' not found