Operating System: Windows 7

Rstudio version: 1.1.383

R version 3.4.2

I have followed this https://github.com/stan-dev/rstan/wiki/Installing-RStan-on-Windows

and got the value 10 at the end, so I assume I am ok on the install part.

**I then opened Rstudio, saved a new script under test.stan**

**Below is the beginning of the script (I took it from a paper just to test how to run):**

library(“rstan”)

// Set up the true parameter values

a = c(.8, 1)

b = c(2, .1)

sigma = .2

// Simulate data

x = (1:1000)/100

N = length(x)

ypred = a[1]*exp(-b[1]*x) + a[2]*exp(-b[2]*x)*

y = ypredexp(rnorm(N, 0, sigma))

**I ran those lines and got this error:**

PARSER EXPECTED: whitespace to end of file.

FOUND AT line 1:

library(“rstan”)

// Set up the true parameter values

a = c(.8, 1)

b = c(2, .1)

sigma = .2

// Simulate data

x = (1:1000)/100

N = length(x)

ypred = a[1]*exp(-b[1]*x) + a[2]*exp(-b[2]*x)*

y = ypredexp(rnorm(N, 0, sigma))

Error in stanc(model_code = paste(program, collapse = “\n”), model_name = model_cppname, :

failed to parse Stan model ‘test’ due to the above error.

**I am not sure what is wrong, any help would be greatly appreciated.**

If I understand correctly, the contents of your `test.stan`

file are as follows:

```
library(“rstan”)
// Set up the true parameter values
a = c(.8, 1)
b = c(2, .1)
sigma = .2
// Simulate data
x = (1:1000)/100
N = length(x)
ypred = a[1]*exp(-b[1]*x) + a[2]*exp(-b[2]x)
y = ypredexp(rnorm(N, 0, sigma))
```

That’s not Stan syntax, that’s R syntax.

Thanks for the reply

**I just run this part again in RStudio with .R extension**

# Set up the true parameter values

a <- c(.8, 1)

b <- c(2, .1)

sigma <- .2

# Simulate data

x <- (1:1000)/100

N <- length(x)

ypred <- a[1]*exp(-b[1]*x) + a[2]*exp(-b[2]*x)*

y <- ypredexp(rnorm(N, 0, sigma))

**And no errors **

**and then I ran the below as test.stan inside Rstudio**

# Fit the model

library(“rstan”)

fit <- stan(“exponentials.stan”, data=list(N=N, x=x, y=y), iter=1000, chains=4)

print(fit, pars=c(“a”, “b”, “sigma”))

**And received this error.**

PARSER EXPECTED: whitespace to end of file.

FOUND AT line 1:

library(“rstan”)

fit <- stan(“exponentials.stan”, data=list(N=N, x=x, y=y), iter=1000, chains=4)

print(fit, pars=c(“a”, “b”, “sigma”))

Error in stanc(model_code = paste(program, collapse = “\n”), model_name = model_cppname, :

failed to parse Stan model ‘test’ due to the above error.

I would like to run it in Rstudio

First, **this isn’t Stan code**:

```
library(“rstan”)
fit <- stan(“exponentials.stan”, data=list(N=N, x=x, y=y), iter=1000, chains=4)
print(fit, pars=c(“a”, “b”, “sigma”))
```

It’s still R code. Do you have a file called “exponentials.stan”? If so, what does it look like?

Judging from the R code that you’ve posted, you’ve been looking at this: http://www.stat.columbia.edu/~gelman/research/published/stan_jebs_2.pdf

It also looks like you’ve confused the R code and the Stan code in that paper. The two are *very* different. You’ll probably need to slow down and read the paper more carefully.

1 Like