rpy2 - 'R' object has no attribute 'nls'

Question

I am using rpy2 to do some non-linear regression in r from python.

import rpy2.robjects as robjects
from rpy2.robjects import DataFrame, Formula
from rpy2.robjec         


        

Answer 1

Consider importing R's stats and base libraries and then replicate needed calls. And use as_formula to convert string representation of formula to actual formula object. Since these are default R libraries find out which method belongs to which package like stats::nls() and base::list().

Notice too in order to keep aligned to Python's syntax rules, any periods in R names are converted to underscores. A few other methods are renamed to avoid clash with Python's own methods.

...
import rpy2.robjects as ro
from rpy2.robjects.packages import importr

base = importr('base', robject_translations={'with': '_with'})
stats = importr('stats', robject_translations={'format_perc': '_format_perc'})

my_formula = stats.as_formula('rates ~ 1-(1/(10^(a * count ^ (b-1))))')

d = ro.ListVector({'a': a, 'b': b})

fit = stats.nls(my_formula, weights=count, start=d)