ordinal_label_levels {eHDPrep}

Extract labels and levels of ordinal variables in a dataset

Description

This function enables preservation of the text labels for ordinal variables in a dataset in preparation for conversion to a numeric matrix. A table is produced which retains the mappings between the text labels and the numerical labels for future reference.

Usage

ordinal_label_levels(data, out_path = NULL)

Arguments

data

data frame with ordinal variables with labels and levels to be extracted.

out_path

Optional string. Path to write output to. If not supplied, R object will be returned.

Value

Tibble of text label and (numerical) level mappings

Examples

require(magrittr)  # for %>%

# create an example class_tbl object
# note that diabetes_type is classed as ordinal yet is not modified as its
# levels are not pre-coded. It should instead be encoded with encode_ordinals().
tibble::tribble(~"var", ~"datatype",
"patient_id", "id",
"tumoursize", "numeric",
"t_stage", "ordinal_tstage",
"n_stage", "ordinal_nstage",
"diabetes", "factor",
"diabetes_type", "ordinal",
"hypertension", "factor",
"rural_urban", "factor",
"marital_status", "factor",
"SNP_a", "genotype",
"SNP_b", "genotype",
"free_text", "freetext") -> data_types

# show unqiue values for t_stage in pre-QC example_data 
unique(example_data$t_stage)

# apply quality control to example_data
apply_quality_ctrl(example_data, patient_id, data_types,
bin_cats =c("No" = "Yes", "rural" = "urban"),  min_freq = 0.6) %>%
ordinal_label_levels -> res

# examine the labels and levels of t_stage in post-QC example_data
dplyr::filter(res, variable == "t_stage")