Subset draws objects by variables, iterations, chains, and draws indices.

subset_draws(x, ...)

# S3 method for draws_matrix
subset_draws(
  x,
  variable = NULL,
  iteration = NULL,
  chain = NULL,
  draw = NULL,
  regex = FALSE,
  unique = TRUE,
  ...
)

# S3 method for draws_array
subset_draws(
  x,
  variable = NULL,
  iteration = NULL,
  chain = NULL,
  draw = NULL,
  regex = FALSE,
  unique = TRUE,
  ...
)

# S3 method for draws_df
subset_draws(
  x,
  variable = NULL,
  iteration = NULL,
  chain = NULL,
  draw = NULL,
  regex = FALSE,
  unique = TRUE,
  ...
)

# S3 method for draws_list
subset_draws(
  x,
  variable = NULL,
  iteration = NULL,
  chain = NULL,
  draw = NULL,
  regex = FALSE,
  unique = TRUE,
  ...
)

# S3 method for draws_rvars
subset_draws(
  x,
  variable = NULL,
  iteration = NULL,
  chain = NULL,
  draw = NULL,
  regex = FALSE,
  unique = TRUE,
  ...
)

# S3 method for draws
subset(x, ...)

Arguments

x

(draws) A draws object or another R object for which the method is defined.

...

Arguments passed to individual methods (if applicable).

variable

(character vector) The variables to select. All elements of non-scalar variables can be selected at once.

iteration

(integer vector) The iteration indices to select.

chain

(integer vector) The chain indices to select.

draw

(integer vector) The draw indices to be select. Subsetting draw indices will lead to an automatic merging of chains via merge_chains.

regex

(logical) Should variable should be treated as a (vector of) regular expressions? Any variable in x matching at least one of the regular expressions will be selected. Defaults to FALSE.

unique

(logical) Should duplicated selection of chains, iterations, or draws be allowed? If TRUE (the default) only unique chains, iterations, and draws are selected regardless of how often they appear in the respective selecting arguments.

Value

A draws object of the same class as x.

Details

To ensure that multiple consecutive subsetting operations work correctly, subset() repairs the draws object before and after subsetting.

Examples

x <- example_draws() subset_draws(x, variable = c("mu", "tau"))
#> # A draws_array: 100 iterations, 4 chains, and 2 variables #> , , variable = mu #> #> chain #> iteration 1 2 3 4 #> 1 2.0 3.0 1.79 6.5 #> 2 1.5 8.2 5.99 9.1 #> 3 5.8 -1.2 2.56 0.2 #> 4 6.8 10.9 2.79 3.7 #> 5 1.8 9.8 -0.03 5.5 #> #> , , variable = tau #> #> chain #> iteration 1 2 3 4 #> 1 2.8 2.80 8.7 3.8 #> 2 7.0 2.76 2.9 6.8 #> 3 9.7 0.57 8.4 5.3 #> 4 4.8 2.45 4.4 1.6 #> 5 2.8 2.80 11.0 3.0 #> #> # ... with 95 more iterations
subset_draws(x, chain = 2)
#> # A draws_array: 100 iterations, 1 chains, and 10 variables #> , , variable = mu #> #> chain #> iteration 1 #> 1 3.0 #> 2 8.2 #> 3 -1.2 #> 4 10.9 #> 5 9.8 #> #> , , variable = tau #> #> chain #> iteration 1 #> 1 2.80 #> 2 2.76 #> 3 0.57 #> 4 2.45 #> 5 2.80 #> #> , , variable = theta[1] #> #> chain #> iteration 1 #> 1 6.26 #> 2 9.32 #> 3 -0.97 #> 4 12.45 #> 5 9.75 #> #> , , variable = theta[2] #> #> chain #> iteration 1 #> 1 1.0 #> 2 9.4 #> 3 -1.2 #> 4 12.5 #> 5 11.9 #> #> # ... with 95 more iterations, and 6 more variables
subset_draws(x, iteration = 5:10, chain = 3:4)
#> # A draws_array: 6 iterations, 2 chains, and 10 variables #> , , variable = mu #> #> chain #> iteration 1 2 #> 1 -0.03 5.48 #> 2 1.06 2.38 #> 3 3.67 11.82 #> 4 3.51 4.90 #> 5 8.85 0.88 #> #> , , variable = tau #> #> chain #> iteration 1 2 #> 1 11.03 3.0 #> 2 2.70 2.3 #> 3 1.68 4.3 #> 4 0.52 3.1 #> 5 5.96 15.8 #> #> , , variable = theta[1] #> #> chain #> iteration 1 2 #> 1 8.2 -0.91 #> 2 5.0 0.59 #> 3 5.2 18.87 #> 4 3.7 1.50 #> 5 13.1 9.07 #> #> , , variable = theta[2] #> #> chain #> iteration 1 2 #> 1 3.2 3.2 #> 2 4.3 1.1 #> 3 4.1 13.0 #> 4 4.1 6.1 #> 5 4.7 11.6 #> #> # ... with 1 more iterations, and 6 more variables
# extract the first chain twice subset_draws(x, chain = c(1, 1), unique = FALSE)
#> # A draws_array: 100 iterations, 2 chains, and 10 variables #> , , variable = mu #> #> chain #> iteration 1 2 #> 1 2.0 2.0 #> 2 1.5 1.5 #> 3 5.8 5.8 #> 4 6.8 6.8 #> 5 1.8 1.8 #> #> , , variable = tau #> #> chain #> iteration 1 2 #> 1 2.8 2.8 #> 2 7.0 7.0 #> 3 9.7 9.7 #> 4 4.8 4.8 #> 5 2.8 2.8 #> #> , , variable = theta[1] #> #> chain #> iteration 1 2 #> 1 3.96 3.96 #> 2 0.12 0.12 #> 3 21.25 21.25 #> 4 14.70 14.70 #> 5 5.96 5.96 #> #> , , variable = theta[2] #> #> chain #> iteration 1 2 #> 1 0.271 0.271 #> 2 -0.069 -0.069 #> 3 14.931 14.931 #> 4 8.586 8.586 #> 5 1.156 1.156 #> #> # ... with 95 more iterations, and 6 more variables
# extract all elements of 'theta' subset_draws(x, variable = "theta")
#> # A draws_array: 100 iterations, 4 chains, and 8 variables #> , , variable = theta[1] #> #> chain #> iteration 1 2 3 4 #> 1 3.96 6.26 13.3 5.78 #> 2 0.12 9.32 6.3 2.09 #> 3 21.25 -0.97 10.6 15.72 #> 4 14.70 12.45 5.4 2.69 #> 5 5.96 9.75 8.2 -0.91 #> #> , , variable = theta[2] #> #> chain #> iteration 1 2 3 4 #> 1 0.271 1.0 2.1 5.0 #> 2 -0.069 9.4 7.3 8.2 #> 3 14.931 -1.2 5.7 6.0 #> 4 8.586 12.5 2.8 2.7 #> 5 1.156 11.9 3.2 3.2 #> #> , , variable = theta[3] #> #> chain #> iteration 1 2 3 4 #> 1 -0.74 0.22 1.4 5.7 #> 2 0.95 9.68 4.1 3.5 #> 3 1.83 -1.37 -8.3 3.1 #> 4 2.67 11.15 -10.8 3.2 #> 5 3.11 12.72 -27.8 2.6 #> #> , , variable = theta[4] #> #> chain #> iteration 1 2 3 4 #> 1 2.1 -0.73 7.8 4.8 #> 2 7.3 8.11 4.7 7.8 #> 3 1.4 -0.79 6.8 6.1 #> 4 4.4 10.48 6.8 7.9 #> 5 2.0 9.70 12.3 11.3 #> #> # ... with 95 more iterations, and 4 more variables