added function for position_count_bp.R

scripts/plotting/functions/position_count_bp.R

@@ -0,0 +1,125 @@
+#!/usr/bin/env Rscript  
+
+#########################################################
+# TASK: function for barplot showing no. of sites with nsSNP
+# count
+#########################################################
+# load libraries and functions
+library(ggplot2)
+library(data.table)
+library(dplyr)
+
+theme_set(theme_grey())
+#=================================================================
+# site_snp_count_bp(): barplots for no. of sites and nsSNP count
+# input args
+## df containing data to plot
+## df column name containing site/position numbers
+## ...opt args
+
+# TODO:
+# legend params, currently it appears as title
+# visually might be nicer for it to be inside the plot
+#=================================================================
+
+site_snp_count_bp <- function (plotdf
+                               , df_colname = "position"
+                               #, bp_plot_title = ""
+                               #, leg_title = "Legend title"
+                               #, leg_text_size = 20
+                               , axis_text_size = 25
+                               , axis_label_size = 22
+                               , xaxis_title = "Number of nsSNPs"
+                               , yaxis_title = "Number of Sites"){
+  
+  # dim of plotdf
+  cat(paste0("\noriginal df dimensions:"
+             , "\nNo. of rows:", nrow(plotdf)
+             , "\nNo. of cols:", ncol(plotdf)
+             , "\nNow adding column: frequency of mutational positions"))
+  
+  # adding snpcount for each position 
+  setDT(plotdf)[, pos_count := .N, by = .(eval(parse(text = df_colname)))] 
+
+  cat("\nCumulative nssnp count\n"
+  , table(plotdf$pos_count))
+  
+  # calculating total no. of mutations
+  tot_muts = sum(table(plotdf$pos_count))
+  
+  # sanity check
+  if(tot_muts == nrow(plotdf)){
+    cat("\nPASS: total number of mutations match"
+        , "\nTotal no. of nsSNPs:", tot_muts)
+  } else{
+    cat("\nWARNING: total no. of muts = ", tot_muts
+        , "\nExpected = ", nrow(plotdf))
+  }
+  
+  # revised dimensions
+  cat(paste0("\nrevised df dimensions:"
+             , "\nNo. of rows:", nrow(plotdf)
+             , "\nNo. of cols:", ncol(plotdf)))
+  
+  # use group by on pos_count
+  snpsBYpos_df <- plotdf %>%
+    group_by(eval(parse(text = df_colname))) %>%
+    summarize(snpsBYpos = mean(pos_count))
+  
+  cat("\nnssnp count\n"
+      , table(snpsBYpos_df$snpsBYpos))
+  
+  # calculating total no. of sites associated with nsSNPs
+  tot_sites = sum(table(snpsBYpos_df$snpsBYpos))
+  
+  # sanity check
+  if(tot_sites == length(unique(plotdf$position))){
+    cat("\nPASS: total number of mutation sites match"
+        , "\nTotal no. of sites with nsSNPs:", tot_sites)
+  } else{
+    cat("WARNING: total no. of sites = ", tot_sites
+        , "\nExpected = ", length(unique(plotdf$position)))
+  }
+  
+  # FIXME: should really be legend title
+  # but atm being using as plot title
+  my_leg_title = paste0("Total nsSNPs:", tot_muts
+                        , ", Total no. of nsSNPs sites:", tot_sites)
+  bp_plot_title = my_leg_title
+  
+  #-------------
+  # start plot 2
+  #--------------
+  # to make x axis display all positions
+  # not sure if to use with sort or directly
+  my_x = sort(unique(snpsBYpos_df$snpsBYpos)) 
+  
+  g = ggplot(snpsBYpos_df, aes(x = snpsBYpos))
+  OutPlot_pos_count = g + geom_bar(aes (alpha = 0.5)
+                                   , show.legend = FALSE) +
+    scale_x_continuous(breaks = unique(snpsBYpos_df$snpsBYpos)) +
+    geom_label(stat = "count", aes(label = ..count..)
+               , color = "black"
+               , size = 10) +
+    theme(axis.text.x = element_text(size = axis_text_size
+                                     , angle = 0)
+          , axis.text.y = element_text(size = axis_text_size
+                                       , angle = 0
+                                       , hjust = 1)
+          , axis.title.x = element_text(size = axis_label_size)
+          , axis.title.y = element_text(size = axis_label_size)
+          #, legend.position = c(0.73,0.8)
+          #, legend.text = element_text(size = leg_text_size)
+          #, legend.title = element_text(size =  axis_label_size)
+          , plot.title = element_text(size =  axis_label_size)) + 
+    
+    labs(title = bp_plot_title
+      , x = xaxis_title
+      , y = yaxis_title)
+
+  return(OutPlot_pos_count)
+}
+
+########################################################################
+#               			end of function   			   
+########################################################################