The supported image formats depend on your system and Tcl/Tk configuration. Export to PostScript (`.ps`, `.eps`) always works. Export to PDF (`.pdf`) works if the command-line tool `epstopdf` is installed. Export to bitmap formats such as `.png`, `.jpg`, `.bmp`, `.tiff`, or `.gif` may work if supported by your Tcl/Tk environment — this often, but not always, requires the Img Tcl extension.
If a selected format fails, use `.ps` or consider capturing a screenshot.
l_export(widget, filename, width, height)The file path of the exported image.
widget path as a string or as an object handle
path of output file
image width in pixels
image height in pixels
Pressing `Ctrl-P` in a loon plot window also opens an interactive export dialog.
l_export_valid_formats, plot.loon