Flatten Metric Output

Flattens a metric output list into a single-level named list with prefixed column names. This is used by the simulation engine to convert metric outputs into flat columns for results collection.

Usage

flatten_metric_output(output, metric_name)

Arguments

output

The metric output list to flatten.

metric_name

Character string identifying the metric, used as prefix.

Value

A named list with flattened names. Scalar values get names like <metric_name>__<field>. Named numeric vectors get expanded to <metric_name>__<field>__<subname>.

Flattening Rules

• Scalar values become <metric_name>__<field>

• Named numeric vectors expand to <metric_name>__<field>__<subname> for each element

• The double underscore __ is used as a separator consistently

Examples

# Scalar values
flatten_metric_output(list(rmse = 0.5, n_obs = 100L), "my_metric")
#> $my_metric__rmse
#> [1] 0.5
#> 
#> $my_metric__n_obs
#> [1] 100
#> 
# Returns: list(my_metric__rmse = 0.5, my_metric__n_obs = 100L)

# Named numeric vectors are expanded
flatten_metric_output(
  list(params = c(alpha = 0.1, beta = 0.2, gamma = 0.3)),
  "estimates"
)
#> $estimates__params__alpha
#> [1] 0.1
#> 
#> $estimates__params__beta
#> [1] 0.2
#> 
#> $estimates__params__gamma
#> [1] 0.3
#> 
# Returns: list(
#   estimates__params__alpha = 0.1,
#   estimates__params__beta = 0.2,
#   estimates__params__gamma = 0.3
# )