Missing formula in .rds output

Hello All,

I reran a model (below) that I have run successfully but with a larger warmup and more iterations. It seemingly ran normally through all the imputed models and produced a large .rds file, as expected. However, when I try to use the brm(file=…) function to load the new .rds file to my r session, I get the following:

Error in validate_formula(formula, data = data, family = family, autocor = autocor, :
argument “formula” is missing, with no default
Calls: brm → validate_formula
Execution halted

Can anyone figure out what I did to get this missing formula issue?

Thank you for any help that you can provide!

fit21<- brm_multiple(formula = chla_mg_m2 ~ temp+shear+PAR_.5+I(PAR_.5^2)+NH4+NO3+THP+LakeSurfElev_m+water_year+car(W, gr = site,"icar")+mo(DaysSinceLastExposed)+(1+temp+shear+PAR_.5+PAR_.5^2+NH4+NO3+THP+LakeSurfElev_m+water_year+mo(DaysSinceLastExposed)|site),
                     data = imp, data2 = W_impute, 
                     family = gaussian(),
                 prior = set_prior("normal(0,5)", class =  "Intercept")+
                               set_prior("lognormal(0,1)", class = "sd")+
                       set_prior("dirichlet(1,1,1,1)", class = "simo", coef = "moDaysSinceLastExposed1"),
                     control = list(adapt_delta = 0.99),
                     warmup = 3000, iter = 6000, chains = 3,
                     cores = 15,
                     file =  "./Modeling/fit_4_9_2021")

version R version 4.0.3 (2020-10-10)
os Windows 10 x64
system x86_64, mingw32

I usually get the ‘formula is mising’-Error when I have a typo in the filename when I try to use brm(file =…)

Thanks for the suggestion! I checked this unfortunately but that’s not my issue this time.