I am new and have been trying to run Stan in Rmarkdown. I have been able to run my own small bits of code, but now I am trying to run simple linear regression in `rstan`

in an `Rnotebook`

with the standard `cars`

dataset.

I have the following error

is.na() applied to non-(list or vector) of type 'NULL’data with name x is not numeric and not usedis.na() applied to non-(list or vector) of type 'NULL’data with name y is not numeric and not usedError in new_CppObject_xp(fields$.module, fields$.pointer, …) :

Exception: variable does not exist; processing stage=data initialization; variable name=x; base type=vector_d (in ‘model67844d3cb5eb_stan_67845af13b64’ at line 3)

Here is all of my code

```
{r}
library(tidyverse)
library(rstan)
```

### Regression

```
{stan, output.var=simple_regression}
data {
int<lower=0> N;
vector[N] x;
vector[N] y;
}
parameters {
real alpha;
real beta;
real<lower=0> sigma;
}
model {
y ~ normal(alpha + beta * x, sigma);
}
```

```
{r}
#Cars
data(cars)
plot(cars$speed~cars$dist)
y <- select(cars,speed) %>% as.list()
x <- select(cars,dist) %>% as.list()
N <- nrow(cars)
N
str(x)
str(y)
class(y)
simp_lreg <- sampling(simple_regression,
data=list(y,x,N))
rstan::summary(simp_lreg)
```