R Graphical Manual

Browse All

Last data update: 2014.03.03

R: Function to mix sample spectres.

mix.EM

R Documentation

Function to mix sample spectres.

Description

This functions allows to mix grain-size distributions with specified proportions and defined noise levels, for example to test the goodness of the EMMA algorithm.

Usage

mix.EM(EM, proportion, noise, autocorrelation)

Arguments

`EM`	Numeric matrix containing the grain-size distribution definitions. Each definition is in a separate row with variable contributions in columns.
`proportion`	Numeric vector containing the relative proportions of each distribution per sample.
`noise`	Numeric scalar containing optional relative white noise levels.
`autocorrelation`	Numeric scalar specifying the degree of autocorrelation among classes. Autocorrelation is realised as running mean of the specified length. Only odd values are allowed.

Details

The function multiplies each end-member with the respective proportion value, sums the resulting variables, adds uniform noise and normalises the resulting mixed sample to 100 %.

Value

Numeric vector comprising a sample composed of known proportions of end-members.

Author(s)

Michael Dietze, Elisabeth Dietze

Examples

## define end-member loadings and phi vector
EMa.1 <- create.EM(p1 = c(2, 8), p2 = c(1, 0.8), s = c(0.7, 0.3),
                   boundaries = c(0, 11), n = 80)
EMa.2 <- create.EM(p1 = c(4, 7), p2 = c(1.1, 1.4), s = c(0.5, 0.5),
                   boundaries = c(0, 11), n = 80)
EMa   <- rbind(EMa.1, EMa.2)

phi   <- seq(0, 11, length.out = 80)

## mix end-member loadings
sample1 <- mix.EM(EMa, proportion = c(0.3, 0.7))
sample2 <- mix.EM(EMa, proportion = c(0.5, 0.5), noise = 0.1,
                  autocorrelation = 3)

## plot end-member loadings (grey) and resulting samples (black)
plot(phi, EMa.1, type="l", col = "grey")
lines(phi, EMa.2, col = "grey")
lines(phi, sample1)
lines(phi, sample2)

Results


R version 3.3.1 (2016-06-21) -- "Bug in Your Hair"
Copyright (C) 2016 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)

R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type 'license()' or 'licence()' for distribution details.

R is a collaborative project with many contributors.
Type 'contributors()' for more information and
'citation()' on how to cite R or R packages in publications.

Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.

> library(EMMAgeo)
Loading required package: GPArotation
Loading required package: limSolve
Loading required package: shape
Loading required package: shiny
> png(filename="/home/ddbj/snapshot/RGM3/R_CC/result/EMMAgeo/mix.EM.Rd_%03d_medium.png", width=480, height=480)
> ### Name: mix.EM
> ### Title: Function to mix sample spectres.
> ### Aliases: mix.EM
> ### Keywords: EMMA
> 
> ### ** Examples
> 
> ## define end-member loadings and phi vector
> EMa.1 <- create.EM(p1 = c(2, 8), p2 = c(1, 0.8), s = c(0.7, 0.3),
+                    boundaries = c(0, 11), n = 80)
> EMa.2 <- create.EM(p1 = c(4, 7), p2 = c(1.1, 1.4), s = c(0.5, 0.5),
+                    boundaries = c(0, 11), n = 80)
> EMa   <- rbind(EMa.1, EMa.2)
> 
> phi   <- seq(0, 11, length.out = 80)
> 
> ## mix end-member loadings
> sample1 <- mix.EM(EMa, proportion = c(0.3, 0.7))
> sample2 <- mix.EM(EMa, proportion = c(0.5, 0.5), noise = 0.1,
+                   autocorrelation = 3)
> 
> ## plot end-member loadings (grey) and resulting samples (black)
> plot(phi, EMa.1, type="l", col = "grey")
> lines(phi, EMa.2, col = "grey")
> lines(phi, sample1)
> lines(phi, sample2)
> 
> 
> 
> 
> 
> dev.off()
null device 
          1 
>