read_stan_csv gives non reproducible results

Summary:

Importing runs from cmdstan which are exactly the same runs (two calls to cmdstan with the same seed and data, etc.) then one ends up getting numerical differences. Whereas running the sampler in rstan directly twice will give exactly the same. Also, when importing the raw csv file with read.csv2 one does get exactly the same data read in.

Description:

Attached is an example.

Reproducible Steps:

See the zip file

rstan_read_stan_csv_bug.zip

Current Output:

Included in zip file. The 2_14_0/normal_exact_repo_bug.Rout file contains the log demonstrating the problem. The R/normal_exact_repo_bug.Rout log shows that things are OK when everything is run inside RStan.

Expected Output:

Stuff should be the same when imported with read_stan_csv.

RStan Version:

2.14.1

R Version:

3.2.1 (but it also happened on 3.3.2)

Operating System:

RHEL 6.7, but also happened on macOS sierra

Start with the attached rstan_read_stan_csv_bug.zip and reproduce the comparison described in the issue. Inspect the normal_exact_repo_bug.Rout logs and compare read_stan_csv with base R read.csv2 and the direct RStan runs. Done means identifying and correcting the source of the numerical differences so repeated identical CmdStan imports match.