Linear Discriminant Analysis r_wrapper.sh $script_file rm(list = objects() ) ############# FORMAT X DATA ######################### format<-function(data) { ind=NULL for(i in 1 : ncol(data)){ if (is.na(data[nrow(data),i])) { ind<-c(ind,i) } } #print(is.null(ind)) if (!is.null(ind)) { data<-data[,-c(ind)] } data } ########GET RESPONSES ############################### get_resp<- function(data) { resp1<-as.vector(data[,ncol(data)]) resp=numeric(length(resp1)) for (i in 1:length(resp1)) { if (resp1[i]=="Y ") { resp[i] = 0 } if (resp1[i]=="X ") { resp[i] = 1 } } return(resp) } ######## CHARS TO NUMBERS ########################### f_to_numbers<- function(F) { ind<-NULL G<-matrix(0,nrow(F), ncol(F)) for (i in 1:nrow(F)) { for (j in 1:ncol(F)) { G[i,j]<-as.integer(F[i,j]) } } return(G) } ###################NORMALIZING######################### norm <- function(M, a=NULL, b=NULL) { C<-NULL ind<-NULL for (i in 1: ncol(M)) { if (sd(M[,i])!=0) { M[,i]<-(M[,i]-mean(M[,i]))/sd(M[,i]) } # else {print(mean(M[,i]))} } return(M) } ##### LDA DIRECTIONS ################################# lda_dec <- function(data, k){ priors=numeric(k) grandmean<-numeric(ncol(data)-1) means=matrix(0,k,ncol(data)-1) B = matrix(0, ncol(data)-1, ncol(data)-1) N=nrow(data) for (i in 1:k){ priors[i]=sum(data[,1]==i)/N grp=subset(data,data\$group==i) means[i,]=mean(grp[,2:ncol(data)]) #print(means[i,]) #print(priors[i]) #print(priors[i]*means[i,]) grandmean = priors[i]*means[i,] + grandmean } for (i in 1:k) { B= B + priors[i]*((means[i,]-grandmean)%*%t(means[i,]-grandmean)) } W = var(data[,2:ncol(data)]) svdW = svd(W) inv_sqrtW =solve(svdW\$v %*% diag(sqrt(svdW\$d)) %*% t(svdW\$v)) B_star= t(inv_sqrtW)%*%B%*%inv_sqrtW B_star_decomp = svd(B_star) directions = inv_sqrtW%*%B_star_decomp\$v return( list(directions, B_star_decomp\$d) ) } ################ NAIVE BAYES FOR 1D SIR OR LDA ############## naive_bayes_classifier <- function(resp, tr_data, test_data, k=2, tau) { tr_data=data.frame(resp=resp, dir=tr_data) means=numeric(k) #print(k) cl=numeric(k) predclass=numeric(length(test_data)) for (i in 1:k) { grp = subset(tr_data, resp==i) means[i] = mean(grp\$dir) #print(i, means[i]) } cutoff = tau*means[1]+(1-tau)*means[2] #print(tau) #print(means) #print(cutoff) if (cutoff>means[1]) { cl[1]=1 cl[2]=2 } else { cl[1]=2 cl[2]=1 } for (i in 1:length(test_data)) { if (test_data[i] <= cutoff) { predclass[i] = cl[1] } else { predclass[i] = cl[2] } } #print(means) #print(mean(means)) #X11() #plot(test_data,pch=predclass, col=resp) predclass } ################# EXTENDED ERROR RATES ################# ext_error_rate <- function(predclass, actualclass,msg=c("you forgot the message"), pr=1) { er=sum(predclass != actualclass)/length(predclass) matr<-data.frame(predclass=predclass,actualclass=actualclass) escapes = subset(matr, actualclass==1) subjects = subset(matr, actualclass==2) er_esc=sum(escapes\$predclass != escapes\$actualclass)/length(escapes\$predclass) er_subj=sum(subjects\$predclass != subjects\$actualclass)/length(subjects\$predclass) if (pr==1) { # print(paste(c(msg, 'overall : ', (1-er)*100, "%."),collapse=" ")) # print(paste(c(msg, 'within escapes : ', (1-er_esc)*100, "%."),collapse=" ")) # print(paste(c(msg, 'within subjects: ', (1-er_subj)*100, "%."),collapse=" ")) } return(c((1-er)*100, (1-er_esc)*100, (1-er_subj)*100)) } ## Main Function ## files<-matrix("${input}", 1,1, byrow=T) d<-"${cond}" # Number of PC tau<-seq(0,1, by=0.005) #tau<-seq(0,1, by=0.1) for_curve=matrix(-10, 3,length(tau)) ############################################################## test_data_whole_X <-read.delim(files[1,1], row.names=1) #### FORMAT TRAINING DATA #################################### # get only necessary columns test_data_whole_X<-format(test_data_whole_X) oligo_labels<-test_data_whole_X[1:(nrow(test_data_whole_X)-1),ncol(test_data_whole_X)] test_data_whole_X<-test_data_whole_X[,1:(ncol(test_data_whole_X)-1)] X_names<-colnames(test_data_whole_X)[1:ncol(test_data_whole_X)] test_data_whole_X<-t(test_data_whole_X) resp<-get_resp(test_data_whole_X) ldaqda_resp = resp + 1 a<-sum(resp) # Number of Subject b<-length(resp) - a # Number of Escape ## FREQUENCIES ################################################# F<-test_data_whole_X[,1:(ncol(test_data_whole_X)-1)] F<-f_to_numbers(F) FN<-norm(F, a, b) ss<-svd(FN) eigvar<-NULL eig<-ss\$d^2 for ( i in 1:length(ss\$d)) { eigvar[i]<-sum(eig[1:i])/sum(eig) } #print(paste(c("Variance explained : ", eigvar[d]*100, "%"), collapse="")) Z<-F%*%ss\$v ldaqda_data <- data.frame(group=ldaqda_resp,Z[,1:d]) lda_dir<-lda_dec(ldaqda_data,2) train_lda_pred <-Z[,1:d]%*%lda_dir[[1]] ############# NAIVE BAYES CROSS-VALIDATION ############# ### LDA ##### y<-ldaqda_resp X<-F cv<-matrix(c(rep('NA',nrow(test_data_whole_X))), nrow(test_data_whole_X), length(tau)) for (i in 1:nrow(test_data_whole_X)) { # print(i) resp<-y[-i] p<-matrix(X[-i,], dim(X)[1]-1, dim(X)[2]) testdata<-matrix(X[i,],1,dim(X)[2]) p1<-norm(p) sss<-svd(p1) pred<-(p%*%sss\$v)[,1:d] test<- (testdata%*%sss\$v)[,1:d] lda <- lda_dec(data.frame(group=resp,pred),2) pred <- pred[,1:d]%*%lda[[1]][,1] test <- test%*%lda[[1]][,1] test<-matrix(test, 1, length(test)) for (t in 1:length(tau)) { cv[i, t] <- naive_bayes_classifier (resp, pred, test,k=2, tau[t]) } } for (t in 1:length(tau)) { tr_err<-ext_error_rate(cv[,t], ldaqda_resp , c("CV"), 1) for_curve[1:3,t]<-tr_err } dput(for_curve, file="${output}") .. class:: infomark **TIP:** If you want to perform Principal Component Analysis (PCA) on the give numeric input data (which corresponds to the "Source file First in "Generate A Matrix" tool), please use *Multivariate Analysis/Principal Component Analysis* ----- .. class:: infomark **What it does** This tool consists of the module to perform the Linear Discriminant Analysis as described in Carrel et al., 2006 (PMID: 17009873) *Carrel L, Park C, Tyekucheva S, Dunn J, Chiaromonte F, et al. (2006) Genomic Environment Predicts Expression Patterns on the Human Inactive X Chromosome. PLoS Genet 2(9): e151. doi:10.1371/journal.pgen.0020151* ----- .. class:: warningmark **Note** - Output from "Generate A Matrix" tool is used as input file for this tool - Output of this tool contains LDA classification success rates for different values of the turning parameter tau (from 0 to 1 with 0.005 interval). This output file will be used to establish the ROC plot, and you can obtain more detail information from this plot.