Create a draws object supported by the posterior package. These methods are just wrappers around CmdStanR's $draws() method provided for convenience.

# S3 method for CmdStanMCMC
as_draws(x, ...)

# S3 method for CmdStanMLE
as_draws(x, ...)

# S3 method for CmdStanLaplace
as_draws(x, ...)

# S3 method for CmdStanVB
as_draws(x, ...)

# S3 method for CmdStanGQ
as_draws(x, ...)

# S3 method for CmdStanPathfinder
as_draws(x, ...)

Arguments

x

A CmdStanR fitted model object.

...

Optional arguments passed to the $draws() method (e.g., variables, inc_warmup, etc.).

Details

To subset iterations, chains, or draws, use the posterior::subset_draws() method after creating the draws object.

Examples

# \dontrun{
fit <- cmdstanr_example()
as_draws(fit)
#> # A draws_array: 1000 iterations, 4 chains, and 105 variables
#> , , variable = lp__
#> 
#>          chain
#> iteration   1   2   3   4
#>         1 -65 -67 -65 -66
#>         2 -66 -65 -65 -67
#>         3 -65 -65 -65 -65
#>         4 -65 -66 -65 -65
#>         5 -66 -69 -71 -66
#> 
#> , , variable = alpha
#> 
#>          chain
#> iteration     1    2    3    4
#>         1 0.448 0.19 0.36 0.34
#>         2 0.343 0.57 0.28 0.53
#>         3 0.441 0.54 0.56 0.45
#>         4 0.095 0.75 0.19 0.57
#>         5 0.089 0.81 0.57 0.20
#> 
#> , , variable = beta[1]
#> 
#>          chain
#> iteration     1     2     3     4
#>         1 -0.40 -0.13 -0.86 -0.87
#>         2 -0.60 -0.75 -0.39 -0.66
#>         3 -0.46 -1.00 -0.90 -0.61
#>         4 -0.74 -0.72 -0.90 -0.87
#>         5 -0.45 -0.80 -0.71 -0.99
#> 
#> , , variable = beta[2]
#> 
#>          chain
#> iteration     1     2      3     4
#>         1 -0.29 -0.25 -0.041 -0.62
#>         2 -0.70 -0.35 -0.376  0.26
#>         3 -0.12 -0.21 -0.190 -0.23
#>         4 -0.48 -0.34 -0.117 -0.20
#>         5 -0.44 -0.10  0.289 -0.28
#> 
#> # ... with 995 more iterations, and 101 more variables

# posterior's as_draws_*() methods will also work
posterior::as_draws_rvars(fit)
#> # A draws_rvars: 1000 iterations, 4 chains, and 4 variables
#> $lp__: rvar<1000,4>[1] mean ± sd:
#> [1] -66 ± 1.5 
#> 
#> $alpha: rvar<1000,4>[1] mean ± sd:
#> [1] 0.38 ± 0.22 
#> 
#> $beta: rvar<1000,4>[3] mean ± sd:
#> [1] -0.67 ± 0.25  -0.28 ± 0.23   0.69 ± 0.27 
#> 
#> $log_lik: rvar<1000,4>[100] mean ± sd:
#>   [1] -0.517 ± 0.101  -0.399 ± 0.145  -0.501 ± 0.225  -0.446 ± 0.153 
#>   [5] -1.185 ± 0.288  -0.589 ± 0.186  -0.639 ± 0.122  -0.277 ± 0.138 
#>   [9] -0.692 ± 0.164  -0.743 ± 0.239  -0.278 ± 0.126  -0.492 ± 0.239 
#>  [13] -0.656 ± 0.204  -0.362 ± 0.176  -0.278 ± 0.108  -0.274 ± 0.089 
#>  [17] -1.598 ± 0.297  -0.478 ± 0.109  -0.232 ± 0.077  -0.113 ± 0.080 
#>  [21] -0.211 ± 0.089  -0.567 ± 0.147  -0.329 ± 0.142  -0.136 ± 0.067 
#>  [25] -0.452 ± 0.119  -1.523 ± 0.345  -0.305 ± 0.123  -0.445 ± 0.085 
#>  [29] -0.723 ± 0.230  -0.694 ± 0.192  -0.485 ± 0.161  -0.423 ± 0.108 
#>  [33] -0.407 ± 0.124  -0.063 ± 0.050  -0.584 ± 0.183  -0.324 ± 0.134 
#>  [37] -0.702 ± 0.231  -0.309 ± 0.148  -0.179 ± 0.111  -0.681 ± 0.127 
#>  [41] -1.135 ± 0.256  -0.932 ± 0.194  -0.410 ± 0.262  -1.177 ± 0.192 
#>  [45] -0.359 ± 0.120  -0.580 ± 0.127  -0.301 ± 0.127  -0.324 ± 0.084 
#>  [49] -0.318 ± 0.082  -1.290 ± 0.332  -0.287 ± 0.095  -0.833 ± 0.145 
#>  [53] -0.400 ± 0.130  -0.372 ± 0.143  -0.382 ± 0.133  -0.319 ± 0.194 
#>  [57] -0.658 ± 0.119  -0.953 ± 0.354  -1.365 ± 0.337  -0.978 ± 0.163 
#>  [61] -0.541 ± 0.099  -0.872 ± 0.313  -0.116 ± 0.075  -0.903 ± 0.248 
#>  [65] -2.029 ± 0.603  -0.508 ± 0.136  -0.276 ± 0.083  -1.064 ± 0.237 
#>  [69] -0.435 ± 0.086  -0.639 ± 0.237  -0.609 ± 0.205  -0.461 ± 0.167 
#>  [73] -1.492 ± 0.362  -0.948 ± 0.200  -1.139 ± 0.388  -0.374 ± 0.142 
#>  [77] -0.878 ± 0.139  -0.489 ± 0.172  -0.766 ± 0.193  -0.539 ± 0.194 
#>  [81] -0.161 ± 0.098  -0.220 ± 0.134  -0.343 ± 0.083  -0.275 ± 0.093 
#>  [85] -0.130 ± 0.076  -1.131 ± 0.318  -0.823 ± 0.128  -0.777 ± 0.238 
#>  [89] -1.284 ± 0.315  -0.258 ± 0.133  -0.384 ± 0.127  -1.503 ± 0.353 
#>  [93] -0.736 ± 0.221  -0.318 ± 0.090  -0.387 ± 0.113  -1.578 ± 0.293 
#>  [97] -0.431 ± 0.102  -1.055 ± 0.371  -0.693 ± 0.139  -0.391 ± 0.098 
#> 
posterior::as_draws_list(fit)
#> # A draws_list: 1000 iterations, 4 chains, and 105 variables
#> 
#> [chain = 1]
#> $lp__
#>  [1] -65 -66 -65 -65 -66 -66 -65 -64 -65 -65
#> 
#> $alpha
#>  [1] 0.448 0.343 0.441 0.095 0.089 0.680 0.373 0.327 0.441 0.215
#> 
#> $`beta[1]`
#>  [1] -0.40 -0.60 -0.46 -0.74 -0.45 -0.80 -0.65 -0.85 -0.39 -0.36
#> 
#> $`beta[2]`
#>  [1] -0.29 -0.70 -0.12 -0.48 -0.44 -0.14 -0.50 -0.33 -0.25 -0.33
#> 
#> 
#> [chain = 2]
#> $lp__
#>  [1] -67 -65 -65 -66 -69 -68 -67 -67 -68 -69
#> 
#> $alpha
#>  [1]  0.186  0.574  0.536  0.753  0.813 -0.010  0.027  0.027  0.628  0.271
#> 
#> $`beta[1]`
#>  [1] -0.126 -0.754 -1.000 -0.716 -0.801 -0.503 -0.628 -0.628 -0.985 -0.052
#> 
#> $`beta[2]`
#>  [1] -0.25 -0.35 -0.21 -0.34 -0.10 -0.34 -0.17 -0.17 -0.70 -0.21
#> 
#> # ... with 990 more iterations, and 2 more chains, and 101 more variables
# }