How to colourise some cell borders in R corrplot?

Question

I would like to keep some cells in attention by making their borders clearly distinct from anything else.

The parameter rect.col is used to colorise all bor

Answer 1

My proposal where still pseudocode mark.ids. I found best to have plt and mark.ids as the options of corrplotCellBorders which creates corrplot with bordered wanted cells

mark.ids <- {x <- c(1), y <- c(2)} # TODO pseudocode
corrplotCellBorders(plt, mark.ids)
cb(plt, x, y, rectArgs=list(border="red", lwd=3))

# Chat of https://stackoverflow.com/q/40538304/54964 user20650
# createBorders.r, test.createBorders. 
cb <- function(corrPlot, ..., rectArgs = list() ){ 
# ... pass named vector of x and y names 
# for upper x > y, lower x < y 
  lst <- list(...) 

  n <- ncol(corrPlot) 
  nms <- colnames(corrPlot) 
  colnames(corrPlot) <- if(is.null(nms)) 1:ncol(corrPlot) else nms 

  xleft <- match(lst$x, colnames(corrPlot)) - 0.5 
  ybottom <- n - match(lst$y, colnames(corrPlot)) + 0.5 

  lst <- list(xleft=xleft, ybottom=ybottom, xright=xleft+1, ytop=ybottom+1) 
  do.call(rect, c(lst, rectArgs)) 
}

corrplotCellBorders <- function(plt, mark.ids) {
  x <- mark.ids$x
  y <- mark.ids$y
  cb(plt, x, y, rectArgs=list(border="red", lwd=3))
}

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