spmap

[Jin Zhang]

Hi, I would like to draw a map of Australia to show the population in each area. However, as you can see from the following graph, the area ACT is surrounded by the area NSW. Consequently, although the population in ACT is only 0.4 million, the area is still filled with dark blue color, the color for NSW (with a population of 8 million). Does anyone have any idea how I can fill the area of ACT with the correct color?

[Scott Merryman]

Jin Zhang

The problem is that spmap does not know the ACT polygon is completely enclosed in another polygon. You need to add a variable called _EMBEDDED to the base map dataset. See the spmap help file "Spatial data format."

For example:

copy https://www.abs.gov.au/statistics/standards/australian-statistical-geography-standard-asgs-edition-3/jul2021-jun2026/access-and-downloads/digital-boundary-files/STE_2021_AUST_SHP_GDA2020.zip aust.zip, replace
unzipfile aust.zip, replace

spshape2dta STE_2021_AUST_GDA2020, replace
use  STE_2021_AUST_GDA2020_shp.dta
gen  _EMBEDDED = 0
replace  _EMBEDDED = 1 if _ID == 8
save,replace


use STE_2021_AUST_GDA2020.dta
spmap AREA using STE_2021_AUST_GDA2020_shp.dta, id(_ID) clm(u) legend(off) fcolor(Rainbow)

[Jin Zhang]

Thank you so much, Scott!