"R" : Identifying peaks

December 13, 2012

(This article was first published on NIR-Quimiometria, and kindly contributed to R-bloggers)

The function "identify"  from "R",  is very useful to check the spectrum for peaks or areas of interest. I use it here to see the wavelength with the highest variability in the Shootout-2012 Calibration Set.

This wavelength has a high variability due to the changes in concentration of the Active component in the mixture.

See the video to see how I use the function:

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We can use the identify option to check for the variables in X with the highest extreme loadings. In this case I use the element "rotation" generated by the object "prcomp".

Let´s use the same salple set as before: Shootout-2012 Calibration Set, and see the video:

As you can see the 216 value has the extreme value in both plots.

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