Remove values from an existing extract definition for an IPUMS microdata project

Remove existing values from an IPUMS microdata extract definition. All fields are optional, and if omitted, will be unchanged.

This function is marked as experimental because it is typically not the best option for maintaining reproducible extract definitions and may be retired in the future. For reproducibility, users should strive to build extract definitions with define_extract_*() functions.

If you have a complicated extract definition to revise, but do not have the original extract definition code that created it, we suggest that you save the revised extract as a JSON file with save_extract_as_json(). This will create a stable version of the extract definition that can be used in the future as needed.

To add new values to an IPUMS microdata extract definition, see add_to_extract().

Learn more about the IPUMS API in vignette("ipums-api").

Usage

# S3 method for micro_extract
remove_from_extract(extract, samples = NULL, variables = NULL, ...)

Arguments

extract

An ipums_extract object.

samples

Character vector of sample names to remove from the extract definition.

variables

Names of the variables to remove from the extract definition. All variable-specific fields for the indicated variables will also be removed.

...

Ignored

Value

A modified micro_extract object

Details

If the supplied extract definition comes from a previously submitted extract request, this function will reset the definition to an unsubmitted state.

To retain a variable while modifying its particular specifications, first remove that variable, then add a new specification using add_to_extract().

See also

add_to_extract() to add values to an extract definition.

submit_extract() and download_extract() to submit and process an extract request.

define_extract_*() to create a new extract definition from scratch.

Examples

usa_extract <- define_extract_usa(
  description = "USA example",
  samples = c("us2013a", "us2014a"),
  variables = list(
    var_spec("AGE", data_quality_flags = TRUE),
    var_spec("SEX", case_selections = "1"),
    "RACE"
  )
)

# Providing names of samples or variables will remove them and
# all of their associated specifications from the extract:
remove_from_extract(
  usa_extract,
  samples = "us2014a",
  variables = c("AGE", "RACE")
)
#> Unsubmitted IPUMS USA extract 
#> Description: USA example
#> 
#> Samples: (1 total) us2013a
#> Variables: (1 total) SEX

# To remove detailed specifications from a variable, indicate the
# specifications to remove within `var_spec()`. The
# named variable will be retained in the extract, but modified by
# removing the indicated specifications.
remove_from_extract(
  usa_extract,
  variables = var_spec("SEX", case_selections = "1")
)
#> Unsubmitted IPUMS USA extract 
#> Description: USA example
#> 
#> Samples: (2 total) us2013a, us2014a
#> Variables: (3 total) AGE, SEX, RACE

# To make multiple modifications, use a list of `var_spec()` objects.
remove_from_extract(
  usa_extract,
  variables = list(
    var_spec("SEX", case_selections = "1"),
    var_spec("AGE")
  )
)
#> Unsubmitted IPUMS USA extract 
#> Description: USA example
#> 
#> Samples: (2 total) us2013a, us2014a
#> Variables: (2 total) SEX, RACE