I am apologize for non-bioinformatic question. I am trying to use these commands for visualize pearson correlation plot with circle + black number corrplot(x.cor, order = "original", type = "upper", tl.pos = "tp") corrplot(x.cor, add = TRUE, type = "lower", method = "number", order = "original", col = "black", diag = FALSE, tl.pos = "n", cl.pos = "n") f irst command is well performed but I have problem for second command with below error and white window (quartz 2) without plot: Error in strwidth("W", cex = tl.cex) : plot.new has not been called yet Thank you very very much in advance for your answers.