Map Projections using Python's pyProj

[Scott Merryman]

As an extension form this post: https://www.statalist.org/forums/for...-with-lat-long

one can use Python's pyProj to create additional map projections that not available in Richard Picard's -geo2xy-.

For example the Chamberlin trimetric projection or the Tobler-Mercator:

clear*

//Note: spshape2dta cannot transform version 5.0
copy "https://www.naturalearthdata.com/http//www.naturalearthdata.com/download/110m/cultural/ne_110m_admin_0_countries.zip?version=4.1.0" map.zip, replace
unzipfile map.zip,replace
spshape2dta ne_110m_admin_0_countries

use ne_110m_admin_0_countries_shp

//Tobler-Mercator
//transformer = pyproj.Proj("+proj=tobmerc")
python:
from sfi import Data
x = Data.get('_X')
y  = Data.get('_Y')

import pyproj
#Chamberlin trimetric projection
transformer = pyproj.Proj("+proj=chamb +lat_1=10 +lon_1=30 +lon_2=40")
x1, y1 = transformer(x, y)
x1, y1 = transformer(x, y)

Data.addVarDouble("x1")
Data.addVarDouble("y1")
Data.store("x1", None, x1)
Data.store("y1", None, y1)
end

replace x1 = . if _X ==.
replace y1 = . if _Y == .
drop _X _Y
rename (y1 x1 ) (_Y _X)
save ne_110m_admin_0_countries_shp2, replace

use ne_110m_admin_0_countries
colorpalette viridis, n(15) nograph
local colors `r(p)'

spmap GDP_MD using  ne_110m_admin_0_countries_shp2, id(_ID)  fcolor("`colors'") osize(0.04 ..) /// 
    cln(15) legend(off) name(map1,replace)

[Jared Greathouse]

Sounds like a Python and Stata problem