R/BGLR_VS.R

In lfmerrick21/WhEATBreeders: Wrappers for Genomic Selection

BGLR_VS <- function(train_genotypes, train_phenotype,train_PCA=NULL,train_CV=NULL,test_genotypes,test_phenotype,test_PCA=NULL,test_CV=NULL,model="RKHS",Kernel="Markers",markers=NULL, nIter = 15000, burnIn = 5000,Sparse=FALSE,m=NULL,degree=NULL, nL=NULL,transformation=NULL)
{

  # Make the CV list

    if(Kernel=="Markers"){
      if(!is.null(markers)){
        genotypes=rbind(train=train_genotypes,test=test_genotypes)
        samp=sample(1:ncol(genotypes), markers)
        genotypes=genotypes[,samp]
      }else{
        genotypes <- genotypes
        genotypes=rbind(train=train_genotypes,test=test_genotypes)
      }


    }else{
      genotypes=rbind(train=train_genotypes,test=test_genotypes)
      maf <- calc_maf_apply(genotypes, encoding = c(0, 1, 2))
      mono_indices <- which(maf ==0)
      if(length(mono_indices)!=0){
        genotypes = genotypes[,-mono_indices]
      }

      if(Sparse==TRUE){
        X=as.matrix(genotypes)
        X=apply(genotypes,2,as.numeric)
        #sum(rowSums(is.na(X)))
        XS<-scale(X,center=TRUE,scale=TRUE)
        #sum(rowSums(is.na(XS)))
        library(caret)
        nzv <- nearZeroVar(XS)
        XSZV <- XS[, -nzv]
        #sum(rowSums(is.na(XSZV)))
        X=XSZV
        K=Sparse_Kernel_Construction(m=m,X=X,name=Kernel, degree=degree,nL=nL)
      }else{
        X=as.matrix(genotypes)
        X=apply(genotypes,2,as.numeric)
        #sum(rowSums(is.na(X)))
        XS<-scale(X,center=TRUE,scale=TRUE)
        #sum(rowSums(is.na(XS)))
        library(caret)
        nzv <- nearZeroVar(XS)
        XSZV <- XS[, -nzv]
        #sum(rowSums(is.na(XSZV)))
        X=XSZV
        K=Kernel_computation(X=X,name=Kernel,degree=degree, nL=nL)
      }

    }
    # Split into training and testing data
    if(transformation=="sqrt"){
      train_phenotype[,2]=replace(train_phenotype[,2], train_phenotype[,2] < 0, 0)
      test_phenotype[,2]=replace(test_phenotype[,2], test_phenotype[,2] < 0, 0)
      train_phenotype[,2] <-sqrt(train_phenotype[,2])
      test_phenotype[,2] <-sqrt(test_phenotype[,2])
      pheno_test=test_phenotype
      pheno_test[,2]<-NA
      pheno_train <- c(train=train_phenotype[,2],test=pheno_test[,2])
    }

    if(transformation=="log"){
      train_phenotype[,2]=replace(train_phenotype[,2], train_phenotype[,2] <= 0, 0.000001)
      test_phenotype[,2]=replace(test_phenotype[,2], test_phenotype[,2] <= 0, 0.000001)
      train_phenotype[,2] <-log(train_phenotype[,2])
      test_phenotype[,2] <-log(test_phenotype[,2])
      pheno_test=test_phenotype
      pheno_test[,2]<-NA
      pheno_train <- c(train=train_phenotype[,2],test=pheno_test[,2])
    }

    if(transformation=="boxcox"){
      train_phenotype[,2] <-boxcox_t(train_phenotype[,2])
      test_phenotype[,2] <-boxcox_t(test_phenotype[,2])
      pheno_test=test_phenotype
      pheno_test[,2]<-NA
      pheno_train <- c(train=train_phenotype[,2],test=pheno_test[,2])
    }

    if(transformation=="none"){
      pheno_test=test_phenotype
      pheno_test[,2]<-NA
      pheno_train <- c(train=train_phenotype[,2],test=pheno_test[,2])

    }


    if(length(train_CV)==0){

      if(!is.null(train_PCA)){
        PCA<-rbind(train=train_PCA,test=test_PCA)
        if(Kernel=="Markers"){
          ETA<-list(list(X=PCA,model="FIXED"),G=list(X=as.matrix(genotypes),model=model))
          BGLR_results <- BGLR(y = pheno_train, ETA = ETA, nIter=nIter, burnIn=burnIn)
          predictions <- predict(BGLR_results)}
        else{
          ETA<-list(list(X=PCA,model="FIXED"),G=list(K=K,model=model))
          BGLR_results <- BGLR(y = pheno_train, ETA = ETA, nIter=nIter, burnIn=burnIn)
          predictions <- predict(BGLR_results)
        }
        acc <- cor(predictions[-c(1:length(train_phenotype[,2]))], test_phenotype[,2], use = "pairwise.complete")
        sacc <- cor(predictions[-c(1:length(train_phenotype[,2]))], test_phenotype[,2], use = "pairwise.complete", method = c("spearman"))
        metrics=postResample(pred=predictions[-c(1:length(train_phenotype[,2]))],obs=test_phenotype[,2])
        results=c(ACC=acc,SACC=sacc,metrics)
        prediction=data.frame(test_phenotype,GEBV=predictions[-c(1:length(train_phenotype[,2]))])
      }else{
        if(Kernel=="Markers"){
          ETA<-list(G=list(X=as.matrix(genotypes),model=model))
          BGLR_results <- BGLR(y = pheno_train, ETA = ETA, nIter=nIter, burnIn=burnIn)
          predictions <- predict(BGLR_results)
        }else{

          ETA<-list(G=list(K=K,model=model))
          BGLR_results <- BGLR(y = pheno_train, ETA = ETA, nIter=nIter, burnIn=burnIn)
          predictions <- predict(BGLR_results)

        }
        acc <- cor(predictions[-c(1:length(train_phenotype[,2]))], test_phenotype[,2], use = "pairwise.complete")
        sacc <- cor(predictions[-c(1:length(train_phenotype[,2]))], test_phenotype[,2], use = "pairwise.complete", method = c("spearman"))
        metrics=postResample(pred=predictions[-c(1:length(train_phenotype[,2]))],obs=test_phenotype[,2])
        results=c(ACC=acc,SACC=sacc,metrics)
        prediction=data.frame(test_phenotype,GEBV=predictions[-c(1:length(train_phenotype[,2]))])

      }
    }else{

      CV<-rbind(train=train_CV,test=test_CV)

      if(!is.null(train_PCA)){
        PCA<-rbind(train=train_PCA,test=test_PCA)

        fix_PC=as.matrix(cbind(CV,PCA))


        if(Kernel=="Markers"){
          ETA<-list(list(X=fix_PC,model="FIXED"),G=list(X=as.matrix(genotypes),model=model))
          BGLR_results <- BGLR(y = pheno_train, ETA = ETA, nIter=nIter, burnIn=burnIn)
          predictions <- predict(BGLR_results)
        }else{
          ETA<-list(list(X=fix_PC,model="FIXED"),G=list(K=K,model=model))
          BGLR_results <- BGLR(y = pheno_train, ETA = ETA, nIter=nIter, burnIn=burnIn)
          predictions <- predict(BGLR_results)
        }
        acc <- cor(predictions[-c(1:length(train_phenotype[,2]))], test_phenotype[,2], use = "pairwise.complete")
        sacc <- cor(predictions[-c(1:length(train_phenotype[,2]))], test_phenotype[,2], use = "pairwise.complete", method = c("spearman"))
        metrics=postResample(pred=predictions[-c(1:length(train_phenotype[,2]))],obs=test_phenotype[,2])
        results=c(ACC=acc,SACC=sacc,metrics)
        prediction=data.frame(test_phenotype,GEBV=predictions[-c(1:length(train_phenotype[,2]))])
      }else{
        gc()
        if(Kernel=="Markers"){
          ETA<-list(list(X=CV,model="FIXED"),G=list(X=as.matrix(genotypes),model=model))
          BGLR_results <- BGLR(y = pheno_train, ETA = ETA, nIter=nIter, burnIn=burnIn)
          predictions <- predict(BGLR_results)
        }else{
          ETA<-list(list(X=CV,model="FIXED"),G=list(K=K,model=model))
          BGLR_results <- BGLR(y = pheno_train, ETA = ETA, nIter=nIter, burnIn=burnIn)
          predictions <- predict(BGLR_results)

        }
        acc <- cor(predictions[-c(1:length(train_phenotype[,2]))], test_phenotype[,2], use = "pairwise.complete")
        sacc <- cor(predictions[-c(1:length(train_phenotype[,2]))], test_phenotype[,2], use = "pairwise.complete", method = c("spearman"))
        metrics=postResample(pred=predictions[-c(1:length(train_phenotype[,2]))],obs=test_phenotype[,2])
        results=c(ACC=acc,SACC=sacc,metrics)
        prediction=data.frame(test_phenotype,GEBV=predictions[-c(1:length(train_phenotype[,2]))])

      }

    }

    names(results)<- c("Pearson","Spearman","RMSE","R2","MAE")

    results_ALL=list(Results=results,Predictions=prediction)
  return(results_ALL)
}