R/multiplot.R

In skyhorsetomoon/Trumpet: Transcriptome-guided quality assessment of m6A-seq data

.multiplot <- function(..., plotlist = NULL, file, cols = 1, layout = NULL) {
  
  # Make a list from the ... arguments and plotlist
  plots <- c(list(...), plotlist)
  
  numPlots = length(plots)
  
  # If layout is NULL, then use 'cols' to determine layout
  if (is.null(layout)) {
    # Make the panel ncol: Number of columns of plots nrow: Number of rows
    # needed, calculated from # of cols
    layout <- t(matrix(seq(1, cols * ceiling(numPlots/cols)), ncol = cols, 
                       nrow = ceiling(numPlots/cols)))
  }
  
  if (numPlots == 1) {
    print(plots[[1]])
    
  } else {
    # Set up the page
    grid.newpage()
    pushViewport(viewport(layout = grid.layout(nrow(layout), ncol(layout))))
    
    # Make each plot, in the correct location
    for (i in seq_len(numPlots)) {
      # Get the i,j matrix positions of the regions that contain this subplot
      matchidx <- as.data.frame(which(layout == i, arr.ind = TRUE))
      
      print(plots[[i]], vp = viewport(layout.pos.row = matchidx$row, 
                                      layout.pos.col = matchidx$col))
    }
  }
}