add_grid.RdAdds grid line specifications to the theme of an scplot object.
add_grid(object, ...)An scplot object (class scplot) returned from the scplot()
function.
Line arguments (see element_line()).
An object of class scplot (seescplot()) with modified theme element
to include the specified grid line properties.
The function allows customization of grid lines by passing arguments
similar to those used in element_line(), such as color, size,
and linetype.