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library(vcfR)
## 
##    *****       ***   vcfR   ***       *****
##    This is vcfR 1.13.0 
##      browseVignettes('vcfR') # Documentation
##      citation('vcfR') # Citation
##    *****       *****      *****       *****
library(vegan)
## Loading required package: permute
## Loading required package: lattice
## This is vegan 2.6-4
library(ggplot2)
library(ggpubr)
getwd()
## [1] "/Users/ziqili/Desktop/COMPBIO Project"
list.files(pattern = "vcf")
## [1] "4.13132463-13372463.ALL.chr4_GRCh38.genotypes.20170504.vcf.gz"
## [2] "ALL.chr4_GRCh38.genotypes.20170504.vcf.gz"                    
## [3] "vcf_num_df.csv"                                               
## [4] "vcf_num_df2.csv"
my_vcf <- "4.13132463-13372463.ALL.chr4_GRCh38.genotypes.20170504.vcf.gz"
vcf <- vcfR::read.vcfR(my_vcf, convertNA = T)
## Scanning file to determine attributes.
## File attributes:
##   meta lines: 130
##   header_line: 131
##   variant count: 7497
##   column count: 2513
## 
Meta line 130 read in.
## All meta lines processed.
## gt matrix initialized.
## Character matrix gt created.
##   Character matrix gt rows: 7497
##   Character matrix gt cols: 2513
##   skip: 0
##   nrows: 7497
##   row_num: 0
## 
Processed variant 1000
Processed variant 2000
Processed variant 3000
Processed variant 4000
Processed variant 5000
Processed variant 6000
Processed variant 7000
Processed variant: 7497
## All variants processed
vcf_num <- vcfR::extract.gt(vcf, element = "GT", IDtoRowNames = F, as.numeric = T, convertNA = T)
list.files() 
##  [1] "1000genomes_people_info2-1.csv"                               
##  [2] "4.13132463-13372463.ALL.chr4_GRCh38.genotypes.20170504.vcf.gz"
##  [3] "ALL.chr4_GRCh38.genotypes.20170504.vcf.gz"                    
##  [4] "COMPBIO FInal Project Workflow.Rmd"                           
##  [5] "COMPBIO FInal Project.Rmd"                                    
##  [6] "Compbio Final_report.Rmd"                                     
##  [7] "COMPBIO Project.Rproj"                                        
##  [8] "Compbio-Final_report.docx"                                    
##  [9] "Compbio-Final_report.html"                                    
## [10] "COMPBIO-FInal-Project-Workflow.Rmd"                           
## [11] "datascaled.csv"                                               
## [12] "rsconnect"                                                    
## [13] "vcf_num_df.csv"                                               
## [14] "vcf_num_df2.csv"
vcf_num_t <- t(vcf_num)
vcf_num_df <- data.frame(vcf_num_t)
sample <- row.names(vcf_num_df)
vcf_num_df <- data.frame(sample, vcf_num_df)
getwd() 
## [1] "/Users/ziqili/Desktop/COMPBIO Project"
write.csv(vcf_num_df, file = "vcf_num_df.csv", row.names = F)
list.files()
##  [1] "1000genomes_people_info2-1.csv"                               
##  [2] "4.13132463-13372463.ALL.chr4_GRCh38.genotypes.20170504.vcf.gz"
##  [3] "ALL.chr4_GRCh38.genotypes.20170504.vcf.gz"                    
##  [4] "COMPBIO FInal Project Workflow.Rmd"                           
##  [5] "COMPBIO FInal Project.Rmd"                                    
##  [6] "Compbio Final_report.Rmd"                                     
##  [7] "COMPBIO Project.Rproj"                                        
##  [8] "Compbio-Final_report.docx"                                    
##  [9] "Compbio-Final_report.html"                                    
## [10] "COMPBIO-FInal-Project-Workflow.Rmd"                           
## [11] "datascaled.csv"                                               
## [12] "rsconnect"                                                    
## [13] "vcf_num_df.csv"                                               
## [14] "vcf_num_df2.csv"
pop_meta <- read.csv(file = "1000genomes_people_info2-1.csv")
names(pop_meta)
## [1] "pop"       "super_pop" "sample"    "sex"       "lat"       "lng"
names(vcf_num_df)[1:10]
##  [1] "sample" "X1"     "X2"     "X3"     "X4"     "X5"     "X6"     "X7"    
##  [9] "X8"     "X9"
vcf_num_df2 <- merge(pop_meta, vcf_num_df, by = "sample")
nrow(vcf_num_df) == nrow(vcf_num_df2)
## [1] TRUE
names(vcf_num_df2)[1:15]
##  [1] "sample"    "pop"       "super_pop" "sex"       "lat"       "lng"      
##  [7] "X1"        "X2"        "X3"        "X4"        "X5"        "X6"       
## [13] "X7"        "X8"        "X9"
getwd()
## [1] "/Users/ziqili/Desktop/COMPBIO Project"
write.csv(vcf_num_df2, file = "vcf_num_df2.csv", row.names = F)
list.files()
##  [1] "1000genomes_people_info2-1.csv"                               
##  [2] "4.13132463-13372463.ALL.chr4_GRCh38.genotypes.20170504.vcf.gz"
##  [3] "ALL.chr4_GRCh38.genotypes.20170504.vcf.gz"                    
##  [4] "COMPBIO FInal Project Workflow.Rmd"                           
##  [5] "COMPBIO FInal Project.Rmd"                                    
##  [6] "Compbio Final_report.Rmd"                                     
##  [7] "COMPBIO Project.Rproj"                                        
##  [8] "Compbio-Final_report.docx"                                    
##  [9] "Compbio-Final_report.html"                                    
## [10] "COMPBIO-FInal-Project-Workflow.Rmd"                           
## [11] "datascaled.csv"                                               
## [12] "rsconnect"                                                    
## [13] "vcf_num_df.csv"                                               
## [14] "vcf_num_df2.csv"
invar_omit <- function(x){
  cat("Dataframe of dim",dim(x), "processed...\n")
  sds <- apply(x, 2, sd, na.rm = TRUE)
  i_var0 <- which(sds == 0)
 
  
  cat(length(i_var0),"columns removed\n")
  
  if(length(i_var0) > 0){
     x <- x[, -i_var0]
  }

  return(x) 
}
names(vcf_num_df2)[1:10]
##  [1] "sample"    "pop"       "super_pop" "sex"       "lat"       "lng"      
##  [7] "X1"        "X2"        "X3"        "X4"
vcf_noinvar <- vcf_num_df2
vcf_noinvar <- invar_omit(vcf_noinvar[, -c(1:6)]) 
## Dataframe of dim 2504 7497 processed...
## 1877 columns removed
vcf_noinvar <- invar_omit(vcf_noinvar)
## Dataframe of dim 2504 5620 processed...
## 0 columns removed
vcf_noinvar <- data.frame(vcf_num_df2[, c(1:6)], vcf_noinvar)
dim(vcf_noinvar) 
## [1] 2504 5626
my_meta_N_invar_cols <- 1877
find_NAs <- function(x){
  NAs_TF <-is.na(x)
  i_NA <- which(NAs_TF == TRUE)
  N_NA <- length(i_NA)
  return(i_NA) 
}
N_rows <- nrow(vcf_noinvar)
N_NA <- rep(x=0, times = N_rows)
N_SNPs <- ncol(vcf_noinvar) 
cat("This may take a minutes...")
## This may take a minutes...
for(i in 1:N_rows){
  i_NA <- find_NAs(vcf_noinvar[i,])
  N_NA_i <- length(i_NA)
  N_NA[i] <- N_NA_i 
}
cutoff50 <- N_SNPs*0.5 
percent_NA <- N_NA/N_SNPs*100 
any(percent_NA > 50)
## [1] FALSE
mean(percent_NA)
## [1] 0
my_meta_N_meanNA_rows <- mean(percent_NA)
mean_imputation <- function(df){
  cat("This make take some time...")
  n_cols <- ncol(df)
  for(i in 1:n_cols){
    column_i <- df[, i]
    mean_i <- mean(column_i, na.rm = TRUE)
    NAs_i <- which(is.na(column_i))
    N_NAs <- length(NAs_i)
    column_i[NAs_i] <- mean_i
    df[, i] <- column_i
  }
  return(df)
}
names(vcf_noinvar)[1:10]
##  [1] "sample"    "pop"       "super_pop" "sex"       "lat"       "lng"      
##  [7] "X1"        "X2"        "X3"        "X4"
vcf_noNA <- vcf_noinvar
vcf_noNA[, -c(1:6)] <- mean_imputation(vcf_noinvar[,-c(1:6)])
## This make take some time...
vcf_scaled <- vcf_noNA
vcf_scaled[, -c(1:6)] <- scale(vcf_noNA[, -c(1:6)])
vcf_pca <- prcomp(vcf_scaled[,-c(1:6)])
write.csv(vcf_scaled, file = "datascaled.csv", row.names = F)