diff --git a/meta_data_analysis/combining_df_lig.R b/meta_data_analysis/combining_df_lig.R
new file mode 100644
index 0000000..73afa6e
--- /dev/null
+++ b/meta_data_analysis/combining_df_lig.R
@@ -0,0 +1,385 @@
+#=======================================================================
+# TASK: To combine mcsm and meta data with af and or
+# by filtering for distance to ligand (<10Ang).
+# This script doesn't output anything.
+# This script is sourced from other .R scripts for plotting ligand plots
+
+# Input csv files:
+# 1) mcsm normalised and struct params
+# 2) gene associated meta_data_with_AFandOR
+#=======================================================================
+#%% specify curr dir
+getwd()
+setwd('~/git/LSHTM_analysis/meta_data_analysis/')
+getwd()
+#=======================================================================
+#%% load packages			 
+#require(data.table)
+#require(arsenal)
+#require(compare)
+#library(tidyverse)
+
+# header file
+header_dir = '~/git/LSHTM_analysis/'
+source(paste0(header_dir, '/', 'my_header.R'))
+#%% variable assignment: input and output paths & filenames
+#=======================================================================
+drug = 'pyrazinamide'
+gene = 'pncA'
+gene_match = paste0(gene,'_p.')
+cat(gene_match)
+
+#===========
+# data dir
+#===========
+datadir = '~/git/Data'
+
+#===========
+# input
+#===========
+# infile1: mCSM data
+#indir = '~/git/Data/pyrazinamide/input/processed/'
+indir = paste0(datadir, '/', drug, '/', 'output') # revised {TODO: change in mcsm pipeline}
+#in_filename = 'mcsm_complex1_normalised.csv'
+in_filename = 'pnca_mcsm_struct_params.csv' 
+infile = paste0(indir, '/', in_filename)
+cat(paste0('Reading infile1: mCSM output file', ' ', infile) )
+
+# infile2: gene associated meta data combined with AF and OR
+#indir: same as above
+in_filename_comb = paste0(tolower(gene),  '_meta_data_with_AFandOR.csv')
+infile_comb = paste0(indir, '/', in_filename_comb)
+cat(paste0('Reading infile2: gene associated combined metadata:', infile_comb))
+
+#===========
+# output
+#===========
+# Uncomment if and when required to output
+outdir = paste0(datadir, '/', drug, '/', 'output') #same as indir
+cat('Output dir: ', outdir, '\n')
+#out_filename = paste0(tolower(gene), 'XXX')
+#outfile = paste0(outdir, '/', out_filename)
+#cat(paste0('Output file with full path:', outfile))
+
+#%% end of variable assignment for input and output files
+#=======================================================================
+#%% Read input files
+
+#####################################
+# input file 1: mcsm normalised data
+# output of step 4 mcsm_pipeline
+#####################################
+
+cat('Reading mcsm_data:'
+    , '\nindir: ', indir
+    , '\ninfile_comb: ', in_filename)
+
+mcsm_data = read.csv(infile
+#                     , row.names = 1
+                     , stringsAsFactors = F
+                     , header = T)
+
+cat('Read mcsm_data file:'
+    , '\nNo.of rows: ', nrow(mcsm_data)
+    , '\nNo. of cols:', ncol(mcsm_data))
+
+# clear variables
+rm(in_filename, infile)
+
+str(mcsm_data)
+
+table(mcsm_data$DUET_outcome); sum(table(mcsm_data$DUET_outcome) )
+
+# spelling Correction 1: DUET
+mcsm_data$DUET_outcome[mcsm_data$DUET_outcome=='Stabilizing'] <- 'Stabilising'
+mcsm_data$DUET_outcome[mcsm_data$DUET_outcome=='Destabilizing'] <- 'Destabilising'
+
+# checks: should be the same as above
+table(mcsm_data$DUET_outcome); sum(table(mcsm_data$DUET_outcome) )
+head(mcsm_data$DUET_outcome); tail(mcsm_data$DUET_outcome)
+
+# spelling Correction 2: Ligand
+table(mcsm_data$Lig_outcome); sum(table(mcsm_data$Lig_outcome) )
+
+mcsm_data$Lig_outcome[mcsm_data$Lig_outcome=='Stabilizing'] <- 'Stabilising'
+mcsm_data$Lig_outcome[mcsm_data$Lig_outcome=='Destabilizing'] <- 'Destabilising'
+
+# checks: should be the same as above
+table(mcsm_data$Lig_outcome); sum(table(mcsm_data$Lig_outcome) )
+head(mcsm_data$Lig_outcome); tail(mcsm_data$Lig_outcome)
+
+# muts with opposing effects on protomer and ligand stability
+# excluded from here as it is redundant. 
+# check 'combining_two_df.R' to refer if required.
+#=======================================================================
+#%% !!!Filter data only for mcsm lig!!!
+
+########################### 
+# Filter/subset data 
+# Lig plots < 10Ang
+# Filter the lig plots for Dis_to_lig < 10Ang
+###########################
+
+# check range of distances
+max(mcsm_data$Dis_lig_Ang)
+min(mcsm_data$Dis_lig_Ang)
+
+# count
+table(mcsm_data$Dis_lig_Ang<10)
+
+# subset data to have only values less than 10 Ang
+mcsm_data2 = subset(mcsm_data, mcsm_data$Dis_lig_Ang < 10)
+
+# sanity checks
+max(mcsm_data2$Dis_lig_Ang)
+min(mcsm_data2$Dis_lig_Ang)
+
+# count no of unique positions
+length(unique(mcsm_data2$Position))
+
+# count no of unique mutations
+length(unique(mcsm_data2$Mutationinformation))
+
+# count Destabilisinga and stabilising
+table(mcsm_data2$Lig_outcome) #{RESULT: no of mutations within 10Ang}
+
+#############################
+# Extra sanity check:
+# for mcsm_lig ONLY
+# Dis_lig_Ang should be <10
+#############################
+
+if (max(mcsm_data2$Dis_lig_Ang) < 10){
+  print ("Sanity check passed: lig data is <10Ang")
+}else{
+  print ("Error: data should be filtered to be within 10Ang")
+}
+
+#!!!!!!!!!!!!!!!!!!!!!
+# REASSIGNMENT: so as not to alter the script
+mcsm_data = mcsm_data2
+#!!!!!!!!!!!!!!!!!!!!!
+#=======================================================================
+
+# clear variables
+rm(mcsm_data2)
+
+# count na in each column
+na_count = sapply(mcsm_data, function(y) sum(length(which(is.na(y))))); na_count
+
+# sort by Mutationinformation
+mcsm_data = mcsm_data[order(mcsm_data$Mutationinformation),]
+head(mcsm_data$Mutationinformation)
+
+orig_col = ncol(mcsm_data)
+# get freq count of positions and add to the df
+setDT(mcsm_data)[, occurrence := .N, by = .(Position)] 
+
+cat('Added 1 col: position frequency to see which posn has how many muts'
+    , '\nNo. of cols now', ncol(mcsm_data)
+    , '\nNo. of cols before: ', orig_col)
+
+pos_count_check = data.frame(mcsm_data$Position, mcsm_data$occurrence)
+
+######################################
+# input file2 meta data with AFandOR
+######################################
+cat('Reading combined meta data and AFandOR file:'
+    , '\nindir: ', indir
+    , '\ninfile_comb: ', in_filename_comb)
+
+meta_with_afor <- read.csv(infile_comb
+                      , stringsAsFactors = F
+                      , header = T)
+
+cat('Read mcsm_data file:'
+    , '\nNo.of rows: ', nrow(meta_with_afor)
+    , '\nNo. of cols:', ncol(meta_with_afor))
+
+# clear variables
+rm(in_filename_comb, infile_comb)
+
+str(meta_with_afor)
+
+# sort by Mutationinformation
+head(meta_with_afor$Mutationinformation)
+meta_with_afor = meta_with_afor[order(meta_with_afor$Mutationinformation),]
+head(meta_with_afor$Mutationinformation)
+#=======================================================================
+cat('Begin merging dfs with NAs',
+	, '\n===============================================================')
+
+###########################
+# merging two dfs: with NA
+###########################
+# link col name  = 'Mutationinforamtion'
+cat('Merging dfs with NAs: big df (1-many relationship b/w id & mut)'
+    ,'\nlinking col: Mutationinforamtion'
+    ,'\nfilename: merged_df2')
+
+head(mcsm_data$Mutationinformation)
+head(meta_with_afor$Mutationinformation)
+
+#########
+# a) merged_df2: meta data with mcsm
+#########
+merged_df2 = merge(x = meta_with_afor
+                  , y = mcsm_data
+                  , by = 'Mutationinformation'
+                  , all.y = T)
+
+cat('Dim of merged_df2: '
+    , '\nNo. of rows: ', nrow(merged_df2)
+    , '\nNo. of cols: ', ncol(merged_df2))
+head(merged_df2$Position)
+
+if(nrow(meta_with_afor) == nrow(merged_df2)){
+  cat('nrow(merged_df2) = nrow (gene associated metadata)'
+      ,'\nExpected no. of rows: ',nrow(meta_with_afor) 
+      ,'\nGot no. of rows: ', nrow(merged_df2))
+} else{
+  cat('nrow(merged_df2)!= nrow(gene associated metadata)'
+      , '\nExpected no. of rows after merge: ', nrow(meta_with_afor)
+      , '\nGot no. of rows: ', nrow(merged_df2)
+      , '\nFinding discrepancy')
+  merged_muts_u = unique(merged_df2$Mutationinformation)
+  meta_muts_u = unique(meta_with_afor$Mutationinformation)
+    # find the index where it differs
+  unique(meta_muts_u[! meta_muts_u %in% merged_muts_u])
+}
+
+# sort by Position
+head(merged_df2$Position)
+merged_df2 = merged_df2[order(merged_df2$Position),]
+head(merged_df2$Position)
+
+merged_df2v2 = merge(x = meta_with_afor
+                   , y = mcsm_data
+                   , by = 'Mutationinformation'
+                   , all.x = T) 
+#!=!=!=!=!=!=!=!
+# COMMENT: used all.y since position 186 is not part of the struc,
+# hence doesn't have a mcsm value
+# but 186 is associated with mutation
+#!=!=!=!=!=!=!=!
+
+# should  be False
+identical(merged_df2, merged_df2v2)
+table(merged_df2$Position%in%merged_df2v2$Position)
+
+rm(merged_df2v2)
+
+#########
+# b) merged_df3: remove duplicate mutation information
+#########
+cat('Merging dfs with NAs: small df (removing duplicate muts)'
+    ,'\nCannot trust lineage info from this'
+    ,'\nlinking col: Mutationinforamtion'
+    ,'\nfilename: merged_df3')
+
+#==#=#=#=#=#=#
+# Cannot trust lineage, country from this df as the same mutation
+# can have many different lineages
+# but this should be good for the numerical corr plots
+#=#=#=#=#=#=#=
+merged_df3 = merged_df2[!duplicated(merged_df2$Mutationinformation),] 
+head(merged_df3$Position); tail(merged_df3$Position) # should be sorted
+
+# sanity checks
+# nrows of merged_df3 should be the same as the nrows of mcsm_data
+if(nrow(mcsm_data) == nrow(merged_df3)){
+  cat('PASS: No. of rows match with mcsm_data'
+      ,'\nExpected no. of rows: ', nrow(mcsm_data)
+      ,'\nGot no. of rows: ', nrow(merged_df3))
+} else {
+  cat('FAIL: No. of rows mismatch'
+      , '\nNo. of rows mcsm_data: ', nrow(mcsm_data)
+      , '\nNo. of rows merged_df3: ', nrow(merged_df3))
+}
+
+# counting NAs in AF, OR cols in merged_df3
+# this is becuase mcsm has no AF, OR cols,
+# so you cannot count NAs
+if (identical(sum(is.na(merged_df3$OR))
+              , sum(is.na(merged_df3$pvalue))
+              , sum(is.na(merged_df3$AF)))){
+  cat('PASS: NA count match for OR, pvalue and AF\n')
+  na_count_df3 = sum(is.na(merged_df3$AF))
+  cat('No. of NAs: ', sum(is.na(merged_df3$OR)))
+} else{
+  cat('FAIL: NA count mismatch'
+      , '\nNA in OR: ', sum(is.na(merged_df3$OR))
+      , '\nNA in pvalue: ', sum(is.na(merged_df3$pvalue))
+      , '\nNA in AF:', sum(is.na(merged_df3$AF)))
+}
+#=======================================================================
+#%% merging without NAs
+
+cat('Begin merging dfs without NAs',
+	, '\n===============================================================')
+
+cat('Merging dfs without any NAs: big df (1-many relationship b/w id & mut)'
+    ,'\nlinking col: Mutationinforamtion'
+    ,'\nfilename: merged_df2_comp')
+
+#########
+# c) merged_df2_comp: merging two dfs without NA
+#########
+merged_df2_comp = merged_df2[!is.na(merged_df2$AF),] 
+#merged_df2_comp = merged_df2[!duplicated(merged_df2$Mutationinformation),] 
+
+# sanity check
+cat('Checking nrows in merged_df2_comp')
+if(nrow(merged_df2_comp) == (nrow(merged_df2) - na_count + 1)){
+  cat('PASS: No. of rows match'
+      ,'\nDim of merged_df2_comp: '
+      ,'\nExpected no. of rows: ', nrow(merged_df2) - na_count + 1
+      , '\nNo. of rows: ', nrow(merged_df2_comp)
+      , '\nNo. of cols: ', ncol(merged_df2_comp))
+}else{
+  cat('FAIL: No. of rows mismatch'
+      ,'\nExpected no. of rows: ', nrow(merged_df2) - na_count + 1
+      ,'\nGot no. of rows: ', nrow(merged_df2_comp))
+}
+
+#########
+# d) merged_df3_comp: remove duplicate mutation information
+#########
+merged_df3_comp = merged_df2_comp[!duplicated(merged_df2_comp$Mutationinformation),] 
+
+cat('Dim of merged_df3_comp: '
+    , '\nNo. of rows: ', nrow(merged_df3_comp)
+    , '\nNo. of cols: ', ncol(merged_df3_comp))
+
+# alternate way of deriving merged_df3_comp
+foo = merged_df3[!is.na(merged_df3$AF),]
+# compare dfs: foo and merged_df3_com
+all.equal(foo, merged_df3)
+
+summary(comparedf(foo, merged_df3))
+
+# sanity check
+cat('Checking nrows in merged_df3_comp')
+if(nrow(merged_df3_comp) == nrow(merged_df3)){
+  cat('NO NAs detected in merged_df3 in AF|OR cols'
+      ,'\nNo. of rows are identical: ', nrow(merged_df3))
+} else{
+  if(nrow(merged_df3_comp) == nrow(merged_df3) - na_count_df3) {
+  cat('PASS: NAs detected in merged_df3 in AF|OR cols'
+      , '\nNo. of NAs: ', na_count_df3
+      , '\nExpected no. of rows in merged_df3_comp: ', nrow(merged_df3) - na_count_df3
+      , '\nGot no. of rows: ', nrow(merged_df3_comp))
+  }
+}
+
+#======================================================================= 
+# write_output files
+# Not required as this is a subset of the combining_two_df.R
+#*************************
+# clear variables
+rm(mcsm_data, meta_with_afor, foo, drug, gene, gene_match, indir, merged_muts_u, meta_muts_u, na_count, orig_col, outdir)
+rm(pos_count_check)
+#%% end of script
+#=======================================================================
+
+
diff --git a/meta_data_analysis/combining_df_ps.R b/meta_data_analysis/combining_df_ps.R
new file mode 100644
index 0000000..212a36b
--- /dev/null
+++ b/meta_data_analysis/combining_df_ps.R
@@ -0,0 +1,423 @@
+#=======================================================================
+# TASK: To combine mcsm and meta data with af and or files  
+# Input csv files:
+# 1) mcsm normalised and struct params
+# 2) gene associated meta_data_with_AFandOR
+
+# Output: 
+# 1) muts with opposite effects on stability
+# 2) large combined df including NAs for AF, OR,etc
+# 		Dim: same no. of rows as gene associated meta_data_with_AFandOR
+# 3) small combined df including NAs for AF, OR, etc.
+# 		Dim: same as mcsm data
+# 4) large combined df excluding NAs 
+# 		Dim: dim(#1) - no. of NAs(AF|OR) + 1
+# 5) small combined df excluding NAs
+# 		Dim: dim(#2) - no. of unique NAs - 1
+# This script is sourced from other .R scripts for plotting
+#=======================================================================
+#%% specify curr dir
+getwd()
+setwd('~/git/LSHTM_analysis/meta_data_analysis/')
+getwd()
+#=======================================================================
+#%% load packages
+#require(data.table)
+#require(arsenal)
+#require(compare)
+#library(tidyverse)
+
+# header file
+header_dir = '~/git/LSHTM_analysis/'
+source(paste0(header_dir, '/', 'my_header.R'))
+#=======================================================================
+#%% variable assignment: input and output paths & filenames
+drug = 'pyrazinamide'
+gene = 'pncA'
+gene_match = paste0(gene,'_p.')
+cat(gene_match)
+
+#===========
+# data dir
+#===========
+datadir = '~/git/Data'
+
+#===========
+# input
+#===========
+# infile1: mCSM data
+#indir = '~/git/Data/pyrazinamide/input/processed/'
+indir = paste0(datadir, '/', drug, '/', 'output') # revised {TODO: change in mcsm pipeline}
+#in_filename = 'mcsm_complex1_normalised.csv'
+in_filename = 'pnca_mcsm_struct_params.csv' 
+infile = paste0(indir, '/', in_filename)
+cat(paste0('Reading infile1: mCSM output file', ' ', infile, '\n') )
+
+# infile2: gene associated meta data combined with AF and OR
+#indir: same as above
+in_filename_comb = paste0(tolower(gene),  '_meta_data_with_AFandOR.csv')
+infile_comb = paste0(indir, '/', in_filename_comb)
+cat(paste0('Reading infile2: gene associated combined metadata:', infile_comb, '\n'))
+
+#===========
+# output
+#===========
+# Uncomment if and when required to output
+outdir = paste0(datadir, '/', drug, '/', 'output') #same as indir
+cat('Output dir: ', outdir, '\n')
+#out_filename = paste0(tolower(gene), 'XXX')
+#outfile = paste0(outdir, '/', out_filename)
+#cat(paste0('Output file with full path:', outfile))
+
+#%% end of variable assignment for input and output files
+#=======================================================================
+#%% Read input files
+
+#####################################
+# input file 1: mcsm normalised data
+# output of step 4 mcsm_pipeline
+#####################################
+cat('Reading mcsm_data:'
+    , '\nindir: ', indir
+    , '\ninfile_comb: ', in_filename)
+
+mcsm_data = read.csv(infile
+#                     , row.names = 1
+                     , stringsAsFactors = F
+                     , header = T)
+
+cat('Read mcsm_data file:'
+    , '\nNo.of rows: ', nrow(mcsm_data)
+    , '\nNo. of cols:', ncol(mcsm_data))
+
+# clear variables
+rm(in_filename, infile)
+
+str(mcsm_data)
+
+table(mcsm_data$DUET_outcome); sum(table(mcsm_data$DUET_outcome) )
+
+# spelling Correction 1: DUET
+mcsm_data$DUET_outcome[mcsm_data$DUET_outcome=='Stabilizing'] <- 'Stabilising'
+mcsm_data$DUET_outcome[mcsm_data$DUET_outcome=='Destabilizing'] <- 'Destabilising'
+
+# checks: should be the same as above
+table(mcsm_data$DUET_outcome); sum(table(mcsm_data$DUET_outcome) )
+head(mcsm_data$DUET_outcome); tail(mcsm_data$DUET_outcome)
+
+# spelling Correction 2: Ligand
+table(mcsm_data$Lig_outcome); sum(table(mcsm_data$Lig_outcome) )
+
+mcsm_data$Lig_outcome[mcsm_data$Lig_outcome=='Stabilizing'] <- 'Stabilising'
+mcsm_data$Lig_outcome[mcsm_data$Lig_outcome=='Destabilizing'] <- 'Destabilising'
+
+# checks: should be the same as above
+table(mcsm_data$Lig_outcome); sum(table(mcsm_data$Lig_outcome) )
+head(mcsm_data$Lig_outcome); tail(mcsm_data$Lig_outcome)
+
+# muts with opposing effects on protomer and ligand stability
+table(mcsm_data$DUET_outcome != mcsm_data$Lig_outcome)
+changes = mcsm_data[which(mcsm_data$DUET_outcome != mcsm_data$Lig_outcome),]
+
+# sanity check: redundant, but uber cautious!
+dl_i = which(mcsm_data$DUET_outcome != mcsm_data$Lig_outcome)
+ld_i = which(mcsm_data$Lig_outcome != mcsm_data$DUET_outcome)
+
+cat('Identifying muts with opposite stability effects')
+if(nrow(changes) == (table(mcsm_data$DUET_outcome != mcsm_data$Lig_outcome)[[2]]) & identical(dl_i,ld_i)) {
+  cat('PASS: muts with opposite effects on stability and affinity correctly identified'
+        , '\nNo. of such muts: ', nrow(changes))
+}else {
+  cat('FAIL: unsuccessful in extracting muts with changed stability effects')
+}
+
+#***************************
+# write file: changed muts
+out_filename = 'muts_opp_effects.csv'
+outfile = paste0(outdir, '/', out_filename)
+cat('Writing file for muts with opp effects:'
+    , '\nFilename: ', outfile
+    , '\nPath: ', outdir)
+
+write.csv(changes, outfile)
+#****************************
+# clear variables
+rm(out_filename, outfile)
+rm(changes, dl_i, ld_i)
+
+# count na in each column
+na_count = sapply(mcsm_data, function(y) sum(length(which(is.na(y))))); na_count
+
+# sort by Mutationinformation
+mcsm_data = mcsm_data[order(mcsm_data$Mutationinformation),]
+head(mcsm_data$Mutationinformation)
+
+orig_col = ncol(mcsm_data)
+
+# get freq count of positions and add to the df
+setDT(mcsm_data)[, occurrence := .N, by = .(Position)] 
+
+cat('Added 1 col: position frequency to see which posn has how many muts'
+    , '\nNo. of cols now', ncol(mcsm_data)
+    , '\nNo. of cols before: ', orig_col)
+
+pos_count_check = data.frame(mcsm_data$Position, mcsm_data$occurrence)
+
+#######################################
+# input file 2: meta data with AFandOR
+#######################################
+cat('Reading combined meta data and AFandOR file:'
+    , '\nindir: ', indir
+    , '\ninfile_comb: ', in_filename_comb)
+
+meta_with_afor <- read.csv(infile_comb
+                      , stringsAsFactors = F
+                      , header = T)
+
+cat('Read mcsm_data file:'
+    , '\nNo.of rows: ', nrow(meta_with_afor)
+    , '\nNo. of cols:', ncol(meta_with_afor))
+
+# counting NAs in AF, OR cols
+if (identical(sum(is.na(meta_with_afor$OR))
+              , sum(is.na(meta_with_afor$pvalue))
+              , sum(is.na(meta_with_afor$AF)))){
+  cat('PASS: NA count match for OR, pvalue and AF\n')
+  na_count = sum(is.na(meta_with_afor$AF))
+  cat('No. of NAs: ', sum(is.na(meta_with_afor$OR)))
+} else{
+  cat('FAIL: NA count mismatch'
+      , '\nNA in OR: ', sum(is.na(meta_with_afor$OR))
+      , '\nNA in pvalue: ', sum(is.na(meta_with_afor$pvalue))
+      , '\nNA in AF:', sum(is.na(meta_with_afor$AF)))
+}
+
+# clear variables
+rm(in_filename_comb, infile_comb)
+
+str(meta_with_afor)
+
+# sort by Mutationinformation
+head(meta_with_afor$Mutationinformation)
+meta_with_afor = meta_with_afor[order(meta_with_afor$Mutationinformation),]
+head(meta_with_afor$Mutationinformation)
+#=======================================================================
+cat('Begin merging dfs with NAs',
+	, '\n===============================================================')
+
+###########################
+# merging two dfs: with NA
+###########################
+# link col name  = 'Mutationinforamtion'
+head(mcsm_data$Mutationinformation)
+head(meta_with_afor$Mutationinformation)
+
+cat('Merging dfs with NAs: big df (1-many relationship b/w id & mut)'
+    ,'\nlinking col: Mutationinforamtion'
+    ,'\nfilename: merged_df2')
+
+#########
+# a) merged_df2: meta data with mcsm
+#########
+merged_df2 = merge(x = meta_with_afor
+                  ,y = mcsm_data
+                  , by = 'Mutationinformation'
+                  , all.y = T)
+
+cat('Dim of merged_df2: '
+    , '\nNo. of rows: ', nrow(merged_df2)
+    , '\nNo. of cols: ', ncol(merged_df2))
+head(merged_df2$Position)
+
+# sanity check
+cat('Checking nrows in merged_df2')
+if(nrow(meta_with_afor) == nrow(merged_df2)){
+  cat('nrow(merged_df2) = nrow (gene associated metadata)'
+      ,'\nExpected no. of rows: ',nrow(meta_with_afor) 
+      ,'\nGot no. of rows: ', nrow(merged_df2))
+} else{
+  cat('nrow(merged_df2)!= nrow(gene associated metadata)'
+      , '\nExpected no. of rows after merge: ', nrow(meta_with_afor)
+      , '\nGot no. of rows: ', nrow(merged_df2)
+      , '\nFinding discrepancy')
+  merged_muts_u = unique(merged_df2$Mutationinformation)
+  meta_muts_u = unique(meta_with_afor$Mutationinformation)
+    # find the index where it differs
+  unique(meta_muts_u[! meta_muts_u %in% merged_muts_u])
+}
+
+# sort by Position
+head(merged_df2$Position)
+merged_df2 = merged_df2[order(merged_df2$Position),]
+head(merged_df2$Position)
+
+merged_df2v2 = merge(x = meta_with_afor
+                   ,y = mcsm_data
+                   , by = 'Mutationinformation'
+                   , all.x = T) 
+#!=!=!=!=!=!=!=!
+# COMMENT: used all.y since position 186 is not part of the struc,
+# hence doesn't have a mcsm value
+# but 186 is associated with mutation
+#!=!=!=!=!=!=!=!
+
+# should  be False
+identical(merged_df2, merged_df2v2)
+table(merged_df2$Position%in%merged_df2v2$Position)
+
+rm(merged_df2v2)
+
+#########
+# b) merged_df3:remove duplicate mutation information
+#########
+cat('Merging dfs without NAs: small df (removing muts with no AF|OR associated)'
+    ,'\nCannot trust lineage info from this'
+    ,'\nlinking col: Mutationinforamtion'
+    ,'\nfilename: merged_df3')
+
+#==#=#=#=#=#=#
+# Cannot trust lineage, country from this df as the same mutation
+# can have many different lineages
+# but this should be good for the numerical corr plots
+#=#=#=#=#=#=#=
+merged_df3 = merged_df2[!duplicated(merged_df2$Mutationinformation),] 
+head(merged_df3$Position); tail(merged_df3$Position) # should be sorted
+
+# sanity check
+cat('Checking nrows in merged_df3')
+if(nrow(mcsm_data) == nrow(merged_df3)){
+  cat('PASS: No. of rows match with mcsm_data'
+      ,'\nExpected no. of rows: ', nrow(mcsm_data)
+      ,'\nGot no. of rows: ', nrow(merged_df3))
+} else {
+  cat('FAIL: No. of rows mismatch'
+      , '\nNo. of rows mcsm_data: ', nrow(mcsm_data)
+      , '\nNo. of rows merged_df3: ', nrow(merged_df3))
+}
+
+# counting NAs in AF, OR cols in merged_df3
+# this is becuase mcsm has no AF, OR cols,
+# so you cannot count NAs
+if (identical(sum(is.na(merged_df3$OR))
+              , sum(is.na(merged_df3$pvalue))
+              , sum(is.na(merged_df3$AF)))){
+  cat('PASS: NA count match for OR, pvalue and AF\n')
+  na_count_df3 = sum(is.na(merged_df3$AF))
+  cat('No. of NAs: ', sum(is.na(merged_df3$OR)))
+} else{
+  cat('FAIL: NA count mismatch'
+      , '\nNA in OR: ', sum(is.na(merged_df3$OR))
+      , '\nNA in pvalue: ', sum(is.na(merged_df3$pvalue))
+      , '\nNA in AF:', sum(is.na(merged_df3$AF)))
+}
+#=======================================================================
+#%% merging without NAs
+
+cat('Begin merging dfs without NAs',
+	, '\n===============================================================')
+
+cat('Merging dfs without any NAs: big df (1-many relationship b/w id & mut)'
+    ,'\nlinking col: Mutationinforamtion'
+    ,'\nfilename: merged_df2_comp')
+
+#########
+# c) merged_df2_comp: same as merge 1 but excluding NA
+#########
+merged_df2_comp = merged_df2[!is.na(merged_df2$AF),] 
+#merged_df2_comp = merged_df2[!duplicated(merged_df2$Mutationinformation),] 
+
+# sanity check
+cat('Checking nrows in merged_df2_comp')
+if(nrow(merged_df2_comp) == (nrow(merged_df2) - na_count + 1)){
+  cat('PASS: No. of rows match'
+      ,'\nDim of merged_df2_comp: '
+      ,'\nExpected no. of rows: ', nrow(merged_df2) - na_count + 1
+      , '\nNo. of rows: ', nrow(merged_df2_comp)
+      , '\nNo. of cols: ', ncol(merged_df2_comp))
+}else{
+  cat('FAIL: No. of rows mismatch'
+      ,'\nExpected no. of rows: ', nrow(merged_df2) - na_count + 1
+      ,'\nGot no. of rows: ', nrow(merged_df2_comp))
+}
+
+#########
+# d) merged_df3_comp: remove duplicate mutation information
+#########
+merged_df3_comp = merged_df2_comp[!duplicated(merged_df2_comp$Mutationinformation),] 
+
+cat('Dim of merged_df3_comp: '
+    , '\nNo. of rows: ', nrow(merged_df3_comp)
+    , '\nNo. of cols: ', ncol(merged_df3_comp))
+
+# alternate way of deriving merged_df3_comp
+foo = merged_df3[!is.na(merged_df3$AF),]
+# compare dfs: foo and merged_df3_com
+all.equal(foo, merged_df3)
+
+summary(comparedf(foo, merged_df3))
+
+# sanity check
+cat('Checking nrows in merged_df3_comp')
+if(nrow(merged_df3_comp) == nrow(merged_df3)){
+  cat('NO NAs detected in merged_df3 in AF|OR cols'
+      ,'\nNo. of rows are identical: ', nrow(merged_df3))
+} else{
+  if(nrow(merged_df3_comp) == nrow(merged_df3) - na_count_df3) {
+  cat('PASS: NAs detected in merged_df3 in AF|OR cols'
+      , '\nNo. of NAs: ', na_count_df3
+      , '\nExpected no. of rows in merged_df3_comp: ', nrow(merged_df3) - na_count_df3
+      , '\nGot no. of rows: ', nrow(merged_df3_comp))
+  }
+}
+#======================================================================= 
+#*********************
+# writing 1 file in the style of a loop: merged_df3
+# print(output dir)
+#i = 'merged_df3'
+#out_filename = paste0(i, '.csv')
+#outfile = paste0(outdir, '/', out_filename)
+
+#cat('Writing output file: '
+#    ,'\nFilename: ', out_filename
+#    ,'\nPath: ', outdir)
+
+#template: write.csv(merged_df3, 'merged_df3.csv')
+#write.csv(get(i), outfile, row.names = FALSE)
+#cat('Finished writing: ', outfile
+#    , '\nNo. of rows: ', nrow(get(i))
+#    , '\nNo. of cols: ', ncol(get(i)))
+
+#%% write_output files;  all 4 files: 
+outvars = c('merged_df2'
+             , 'merged_df3'
+             , 'merged_df2_comp'
+             , 'merged_df3_comp')
+
+cat('Writing output files: '
+    , '\nPath:', outdir)
+
+for (i in outvars){
+#  cat(i, '\n')
+  out_filename = paste0(i, '.csv')
+#  cat(out_filename, '\n')
+#  cat('getting value of variable: ', get(i))
+  outfile = paste0(outdir, '/', out_filename)
+#  cat('Full output path: ', outfile, '\n')
+  cat('Writing output file:'
+      ,'\nFilename: ', out_filename,'\n')
+  write.csv(get(i), outfile, row.names = FALSE)
+  cat('Finished writing: ', outfile
+      , '\nNo. of rows: ', nrow(get(i))
+      , '\nNo. of cols: ', ncol(get(i)), '\n')
+}
+
+# alternate way to replace with implicit loop 
+# FIXME
+#sapply(outvars, function(x, y) write.csv(get(outvars), paste0(outdir, '/', outvars, '.csv')))
+#*************************
+# clear variables
+rm(mcsm_data, meta_with_afor, foo, drug, gene, gene_match, indir, merged_muts_u, meta_muts_u, na_count, orig_col, outdir)
+rm(pos_count_check)
+#%% end of script
+#=======================================================================
+