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 -66 -67 -65 -67
#>         2 -65 -65 -64 -67
#>         3 -66 -66 -65 -64
#>         4 -65 -65 -65 -66
#>         5 -67 -67 -66 -65
#> 
#> , , variable = alpha
#> 
#>          chain
#> iteration    1      2    3    4
#>         1 0.37 0.0232 0.30 0.19
#>         2 0.35 0.1359 0.50 0.56
#>         3 0.39 0.0021 0.22 0.42
#>         4 0.42 0.2264 0.22 0.21
#>         5 0.30 0.6367 0.19 0.24
#> 
#> , , variable = beta[1]
#> 
#>          chain
#> iteration     1     2     3     4
#>         1 -0.21 -0.70 -0.87 -0.93
#>         2 -0.42 -0.81 -0.58 -0.38
#>         3 -1.01 -0.83 -0.81 -0.49
#>         4 -0.95 -0.45 -0.67 -1.03
#>         5 -0.16 -0.96 -0.73 -0.89
#> 
#> , , variable = beta[2]
#> 
#>          chain
#> iteration       1     2      3     4
#>         1 -0.3841  0.08 -0.574 -0.73
#>         2 -0.2843 -0.27 -0.376  0.12
#>         3 -0.0223 -0.13 -0.065 -0.11
#>         4  0.0016 -0.28 -0.100 -0.29
#>         5 -0.5327 -0.66 -0.644 -0.16
#> 
#> # ... 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 ± 1.4 
#> 
#> $alpha: rvar<1000,4>[1] mean ± sd:
#> [1] 0.37 ± 0.22 
#> 
#> $beta: rvar<1000,4>[3] mean ± sd:
#> [1] -0.66 ± 0.25  -0.27 ± 0.23   0.67 ± 0.26 
#> 
#> $log_lik: rvar<1000,4>[100] mean ± sd:
#>   [1] -0.518 ± 0.099  -0.405 ± 0.147  -0.501 ± 0.220  -0.451 ± 0.153 
#>   [5] -1.173 ± 0.276  -0.592 ± 0.185  -0.640 ± 0.123  -0.280 ± 0.135 
#>   [9] -0.693 ± 0.163  -0.740 ± 0.234  -0.283 ± 0.124  -0.500 ± 0.241 
#>  [13] -0.655 ± 0.206  -0.364 ± 0.175  -0.282 ± 0.106  -0.278 ± 0.087 
#>  [17] -1.582 ± 0.288  -0.481 ± 0.107  -0.235 ± 0.076  -0.115 ± 0.079 
#>  [21] -0.215 ± 0.088  -0.570 ± 0.144  -0.332 ± 0.140  -0.139 ± 0.067 
#>  [25] -0.456 ± 0.121  -1.513 ± 0.345  -0.309 ± 0.120  -0.447 ± 0.083 
#>  [29] -0.722 ± 0.227  -0.694 ± 0.189  -0.489 ± 0.157  -0.427 ± 0.106 
#>  [33] -0.412 ± 0.126  -0.065 ± 0.052  -0.585 ± 0.184  -0.327 ± 0.135 
#>  [37] -0.700 ± 0.227  -0.314 ± 0.150  -0.182 ± 0.110  -0.681 ± 0.126 
#>  [41] -1.124 ± 0.248  -0.928 ± 0.195  -0.412 ± 0.267  -1.169 ± 0.185 
#>  [45] -0.362 ± 0.119  -0.583 ± 0.128  -0.307 ± 0.129  -0.327 ± 0.084 
#>  [49] -0.322 ± 0.079  -1.286 ± 0.334  -0.291 ± 0.096  -0.833 ± 0.144 
#>  [53] -0.404 ± 0.127  -0.373 ± 0.143  -0.388 ± 0.134  -0.322 ± 0.195 
#>  [57] -0.658 ± 0.117  -0.951 ± 0.353  -1.351 ± 0.337  -0.975 ± 0.159 
#>  [61] -0.542 ± 0.099  -0.876 ± 0.314  -0.119 ± 0.075  -0.901 ± 0.247 
#>  [65] -1.995 ± 0.581  -0.511 ± 0.134  -0.279 ± 0.083  -1.057 ± 0.233 
#>  [69] -0.438 ± 0.083  -0.638 ± 0.235  -0.609 ± 0.207  -0.463 ± 0.169 
#>  [73] -1.476 ± 0.363  -0.944 ± 0.194  -1.139 ± 0.389  -0.376 ± 0.140 
#>  [77] -0.875 ± 0.136  -0.489 ± 0.174  -0.764 ± 0.190  -0.545 ± 0.196 
#>  [81] -0.165 ± 0.100  -0.226 ± 0.138  -0.346 ± 0.081  -0.278 ± 0.091 
#>  [85] -0.132 ± 0.075  -1.120 ± 0.315  -0.822 ± 0.127  -0.773 ± 0.237 
#>  [89] -1.270 ± 0.314  -0.263 ± 0.136  -0.388 ± 0.129  -1.484 ± 0.335 
#>  [93] -0.738 ± 0.218  -0.321 ± 0.088  -0.391 ± 0.110  -1.562 ± 0.280 
#>  [97] -0.433 ± 0.102  -1.052 ± 0.372  -0.693 ± 0.139  -0.393 ± 0.098 
#> 
posterior::as_draws_list(fit)
#> # A draws_list: 1000 iterations, 4 chains, and 105 variables
#> 
#> [chain = 1]
#> $lp__
#>  [1] -66 -65 -66 -65 -67 -65 -65 -64 -67 -69
#> 
#> $alpha
#>  [1]  0.373  0.355  0.389  0.419  0.300  0.178  0.629  0.288  0.016 -0.075
#> 
#> $`beta[1]`
#>  [1] -0.21 -0.42 -1.01 -0.95 -0.16 -0.51 -0.69 -0.67 -0.74 -0.71
#> 
#> $`beta[2]`
#>  [1] -0.3841 -0.2843 -0.0223  0.0016 -0.5327 -0.3040 -0.3392 -0.2792  0.0976
#> [10]  0.1916
#> 
#> 
#> [chain = 2]
#> $lp__
#>  [1] -67 -65 -66 -65 -67 -67 -67 -64 -68 -66
#> 
#> $alpha
#>  [1] 0.0232 0.1359 0.0021 0.2264 0.6367 0.7152 0.4707 0.3940 0.0634 0.4544
#> 
#> $`beta[1]`
#>  [1] -0.70 -0.81 -0.83 -0.45 -0.96 -0.34 -1.17 -0.57 -0.62 -0.62
#> 
#> $`beta[2]`
#>  [1]  0.08 -0.27 -0.13 -0.28 -0.66 -0.57 -0.21 -0.20 -0.47 -0.67
#> 
#> # ... with 990 more iterations, and 2 more chains, and 101 more variables
# }