Hi,

I am struggling to find the appropriate representation of data for arrays of vectors. For a normal vector y[N] I have used

```
y <- c(8.90680694580078,5.51890277862549)
```

but I don’t know how to do this when I have this form:

```
vector[2] y[N];
```

I have tried something like vectors in a vector, which apparently does not work

```
y <- c(c(1,2),c(3,4))
```

and I get the error message

```
"data y value beyond int range"
```

Does anyone have any suggestions?

You should just be able to use an Nx2 matrix (assuming N is 50 here):

`matrix(rnorm(100), nrow = 50, ncol = 2)`

or a list of N length 2 vectors:

```
y = list()
for(n in 1:50) {
y[[n]] = rnorm(2)
}
```

or there’s this strange structure thing that cmdstan uses as input:

```
structure(rnorm(100), .Dim = c(50, 2))
```

One of those seem like what you’re looking for?

Yes, thank you! Didn’t know cmdstan doesn’t like a matrix as input. The structure worked

The exact format is documented in the CmdStan manual. There’s a function in RStan, `stan_rdump`

, that will write data into the format CmdStan expects.