MCR: Class MCR

In tofsims: Import, process and analysis of Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) imaging data

Description

Class MCR contains methods for 'Multivariate Curve Resolution by Alternate Least Squares'

opaMCR is a MCR-ALS function using the Orthogonal Projection Approach from

Usage

opaMCR(dataObject, opaComps, maxiter = 10)

Arguments

dataObject	object of class MassImage
opaComps	numeric number of components for the opa method
maxiter	numeric how many iterations

Details

Class MCR contains methods for 'Multivariate Curve Resolution by Alternate Least Squares'

opaMCR uses the function alsace::opa() (Orthogonal Projection Approach, Bioconductor package 'alsace') for start estimates of pure spectras and ALS::als() (CRAN package 'ALS') as MCR-ALS implementation. This method is doing fine with images up to 256x256 pixels. For larger images, memory usage becomes unreasonably high.

Value

object of class MCR

Slots

RSS

numeric residual sum of squares

resids

matrix with residuals

iters

numeric number of iterations

Author(s)

Lorenz Gerber <[e-mail]>

Examples

testImage<-MassImage('dummy')
testImage<-opaMCR(testImage, 2, 2)
image(analysis(testImage,1), comp = 1)
## Not run: 
library(tofsimsData)
data(tofsimsData)
testImage<-MCR(testImage, 5, 5)
image(analysis(testImage,1), comp = 1)

## End(Not run)

tofsims documentation built on Nov. 8, 2020, 5:10 p.m.