Finding a place on a graphic....

use:

pos2 <- locator()

See: http://stackoverflow.com/questions/19167586/add-text-on-heatmap-using-locator

Things I'm learning at user group

The magick package: Advanced Image-Processing in R
magick
https://cran.r-project.org/web/packages/magick/vignettes/intro.html



broom: a package for tidying statistical models into data frames
https://www.r-bloggers.com/broom-a-package-for-tidying-statistical-models-into-data-frames/