Allow to calculate the relative crystallinity of starch by XRD. The basic concept of Bruckner approach involves obtaining a smoothed line that separates the amorphous and crystalline starch of an Xray diffraction pattern. This smoothed line is achieved by applying a moving average smoothing method to the original pattern.
1  crystMW(pattern, N = 41, iter = 100)

pattern 
matrix. The matrix of Xray diffraction pattern. The first row corresponds to Bragg angle 2θ; the second row corresponds to intensity. 
N 
numeric. N length of the smoothing window (number of variables). Defaults to 41. 
iter 
numeric. Iter number of iterations. Defaults to 100. 
Calculate the relative starch crystallinity of XRD pattern by Bruckner method.
An object of class crystMW, which is a list with the following components:
original 
Original matrix of Xray diffraction patterns. 
background 
Estimation of the background shape (curve of the amorphous starch). 
corrected 
Estimation of residual crystalline area (curve of the crystalline starch). 
summary 
Summary calculation of crystallinity. Total area under the curve of the diffraction pattern (A.U.); Amorphous area (A.U.); Crystalline area (A.U.); Relative crystallinity (%). 
Claudio Pozo Valenzuela [aut, cre] and Saddys Rodriguezllamazares [aut]
Bruckner, S. (2000). "Estimation of the background in powder diffraction patterns through a robust smoothing procedure." Journal of Applied Crystallography 33(3 Part 2): 977979.
1 2 3 4 5 6 7 8 9 10 11 12 13  data(XRD)
# Convert data frame to matrix, select Atype starch
pattern < as.matrix(t(XRD[,c("Bragg_angle","A")]))
# List of crystallinity components
crs < crystMW(pattern, N = 41, iter = 100)
# Original matrix
original < crs$original
# Background shape
background < crs$background
# Curve of the crystalline starch
corrected < crs$corrected
# Summary calculation of crystallinity
summary < crs$summary

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