putPlot(pm, value, i, j)

## S3 replacement method for class 'ggmatrix'
pm[i, j, ...] <- value

# Small function to display plots only if it's interactive
p_ <- GGally::print_if_interactive

custom_car <- ggpairs(mtcars[, c("mpg", "wt", "cyl")], upper = "blank", title = "Custom Example")
# ggplot example taken from example(geom_text)
  plot <- ggplot2::ggplot(mtcars, ggplot2::aes(x=wt, y=mpg, label=rownames(mtcars)))
  plot <- plot +
    ggplot2::geom_text(ggplot2::aes(colour=factor(cyl)), size = 3) +
    ggplot2::scale_colour_discrete(l=40)
custom_car[1, 2] <- plot
personal_plot <- ggally_text(
  "ggpairs allows you\nto put in your\nown plot.\nLike that one.\n <---"
)
custom_car[1, 3] <- personal_plot
# custom_car

# remove plots after creating a plot matrix
custom_car[2,1] <- NULL
custom_car[3,1] <- "blank" # the same as storing null
custom_car[3,2] <- NULL
p_(custom_car)