Vavilov fitting

hi ,

Iam trying to run the file fit_vavilov.C using root 5.27 but all the time it is showing ERROR.
ERROR:Invalid type ‘VavilovAccurate’ in declaration of ‘pdf’ fit_vavilov.C
ERROR:Symbol Vavilovaccurate pdf is not defined in current scope.
please help me to solve this problem.

data.txt (72 KB)
fit_Vavilov.C (911 Bytes)

Duplicate post, see

Fitting a histogram with Vavilov function