Converts factor levels or labelled values to numeric. For factors, uses the underlying integer codes (or the numeric value of levels if they are numeric strings). For labelled variables, extracts the underlying numeric values.
Arguments
- data
A data frame, tibble, or a single vector.
- ...
Optional: unquoted variable names (tidyselect supported). If empty, converts all factor columns.
- use.labels
If
TRUE(default), attempts to use the numeric value of factor levels (e.g., level"3"becomes3). IfFALSE, uses sequential integers (1, 2, 3, ...).- start.at
If not
NULL, the lowest numeric value in the output starts at this number. Default:NULL(use original values).- keep.labels
If
TRUE, the former factor levels are stored as value labels on the result. Default:FALSE.
Value
The input with variables converted to numeric. For single vector input, returns a numeric vector.
Details
This function handles three input types:
Numeric factors (levels like
"1","2","3"): Extracts the numeric values from the level names.Text factors (levels like
"Male","Female"): Converts to sequential integers by default; useuse.labels = FALSEto force this behavior even for numeric-looking levels.haven_labelled: Extracts the underlying numeric vector, stripping the labelled class.
See also
to_label() for the reverse (numeric → factor),
to_labelled() for creating labelled vectors
Other labels:
copy_labels(),
drop_labels(),
find_var(),
set_na(),
to_character(),
to_label(),
to_labelled(),
unlabel(),
val_labels(),
var_label()
Examples
# Numeric factor levels → numeric
x <- factor(c("1", "3", "5", "3"))
to_numeric(x)
#> [1] 1 3 5 3
# [1] 1 3 5 3
# Sequential integers
to_numeric(x, use.labels = FALSE)
#> [1] 1 2 3 2
# [1] 1 2 3 2
# Haven labelled → plain numeric
to_numeric(survey_data$life_satisfaction)
#> [1] 4 3 2 2 4 4 3 3 4 3 1 1 2 5 3 2 3 4 3 3 2 5 1 5
#> [25] 5 2 5 4 5 5 3 3 2 3 5 1 NA 2 3 3 3 2 4 3 3 3 4 3
#> [49] 2 3 3 4 3 3 3 1 4 4 2 5 2 5 4 2 2 5 2 5 5 3 5 NA
#> [73] 2 5 3 2 5 3 5 4 5 2 5 5 5 4 4 NA 5 4 4 5 3 4 3 4
#> [97] 2 NA 5 4 1 4 1 3 4 3 4 2 4 2 4 3 NA 5 2 5 NA 4 4 5
#> [121] 5 3 3 1 3 1 4 4 5 4 4 NA 5 2 3 5 5 4 5 2 3 5 5 5
#> [145] 3 4 5 5 3 5 4 4 5 5 5 2 4 5 3 3 4 4 2 4 5 4 2 1
#> [169] 5 4 3 3 3 4 4 5 4 3 2 4 4 5 4 4 5 4 5 5 NA 2 1 4
#> [193] 4 5 4 4 5 4 2 4 5 1 NA 4 4 NA 1 3 3 5 4 5 3 3 NA 3
#> [217] 4 5 2 3 5 5 5 5 5 2 3 2 4 3 3 4 5 5 5 2 5 NA 5 5
#> [241] 5 5 5 2 2 2 5 4 5 4 3 4 4 5 4 3 5 3 NA 5 5 1 2 5
#> [265] 4 2 2 3 4 1 4 5 5 1 3 4 5 4 3 5 3 4 3 4 4 4 4 3
#> [289] 1 4 3 5 4 4 3 5 5 5 5 2 3 2 3 3 5 4 3 5 4 3 3 3
#> [313] 5 4 3 3 3 NA 5 3 3 1 5 4 4 4 4 5 4 3 4 5 2 4 4 5
#> [337] 5 4 3 3 5 5 4 3 5 4 2 2 4 5 1 3 2 2 3 3 3 5 5 2
#> [361] 5 2 3 3 4 4 5 4 5 5 2 5 5 4 5 1 NA 4 2 4 3 5 3 2
#> [385] 3 3 2 3 3 5 5 5 2 2 2 5 5 4 2 4 4 5 1 1 4 4 3 5
#> [409] 4 5 5 3 4 4 5 3 4 5 3 1 3 3 5 4 4 4 4 4 2 2 2 4
#> [433] 3 4 2 3 4 3 1 4 2 4 5 2 3 3 4 5 NA 4 4 5 5 4 2 1
#> [457] 1 3 3 4 NA 3 2 3 2 4 4 3 4 3 2 5 4 3 3 4 3 4 5 4
#> [481] 1 2 3 4 3 3 2 3 3 3 4 5 4 5 2 5 5 2 5 4 3 2 3 4
#> [505] 4 2 2 5 2 2 4 4 5 3 1 4 3 5 4 5 NA 3 2 5 1 3 3 5
#> [529] 3 4 2 2 3 5 5 3 4 2 5 5 4 5 1 4 5 2 4 5 2 NA 4 4
#> [553] 5 4 4 2 5 4 4 4 3 4 3 3 4 5 3 5 3 4 5 4 3 5 1 4
#> [577] 4 5 1 4 3 5 3 4 NA 3 3 3 3 4 5 5 5 3 5 5 4 3 4 4
#> [601] 3 5 2 5 2 4 5 3 5 2 3 4 3 4 1 4 4 4 5 4 5 3 5 5
#> [625] 3 4 4 5 3 3 5 5 4 5 3 4 2 4 5 4 5 5 4 5 4 3 4 4
#> [649] 1 4 2 4 4 5 NA 1 2 4 5 4 4 NA 4 3 5 5 4 5 2 3 5 3
#> [673] 5 3 4 5 4 4 5 3 3 4 2 5 4 3 2 5 3 3 4 1 5 3 4 4
#> [697] 4 3 4 4 1 4 5 5 3 5 3 3 5 5 4 1 1 3 3 5 NA 3 5 4
#> [721] 5 5 5 3 5 1 5 4 4 4 4 3 4 3 5 5 2 5 5 4 3 1 5 3
#> [745] 3 3 3 2 5 5 4 2 4 2 4 3 3 4 5 5 4 3 3 3 5 5 NA 4
#> [769] 1 1 3 5 4 5 3 4 2 3 2 5 2 5 5 3 3 5 5 4 5 4 5 3
#> [793] 4 4 3 3 5 4 5 3 3 3 NA 4 3 4 3 4 1 3 4 5 1 5 NA 2
#> [817] 3 2 1 5 5 4 5 3 3 5 3 5 1 4 1 5 3 4 3 2 3 4 3 3
#> [841] 4 5 2 5 5 1 3 2 3 2 4 NA 5 3 4 3 5 2 3 4 5 5 4 5
#> [865] 5 3 4 5 4 2 3 1 4 5 4 3 5 4 5 5 5 3 2 4 5 5 4 4
#> [889] 4 2 4 3 1 5 3 4 5 3 4 4 4 NA 4 5 4 4 4 4 3 2 4 4
#> [913] 5 5 5 4 4 5 5 2 3 5 3 5 2 2 2 3 3 4 3 4 4 4 5 5
#> [937] 2 5 5 5 5 4 4 3 2 2 4 4 4 2 3 3 3 3 5 5 4 5 4 5
#> [961] 3 2 5 2 5 3 1 4 2 NA 3 3 2 5 3 2 5 3 4 3 3 4 3 4
#> [985] 2 5 2 2 3 5 3 5 4 4 4 3 3 5 3 3 4 4 3 3 3 5 4 4
#> [1009] 5 4 5 3 4 NA 2 3 5 3 5 5 1 5 4 3 5 4 3 5 4 3 5 4
#> [1033] 5 3 5 3 NA 1 5 4 4 3 2 3 3 4 3 5 3 5 NA 2 3 5 5 1
#> [1057] 2 5 5 4 3 1 3 5 2 3 4 5 5 4 5 4 3 NA 4 4 2 5 2 4
#> [1081] 5 2 3 4 4 3 2 5 2 4 5 3 5 3 4 2 5 3 4 5 4 4 3 5
#> [1105] 3 2 3 5 5 NA 5 5 5 3 2 5 3 3 3 2 4 3 3 5 4 3 5 5
#> [1129] 3 5 4 4 4 5 4 3 5 3 5 5 NA 4 1 3 5 3 5 4 NA 4 4 4
#> [1153] 4 5 5 4 3 4 2 4 4 4 5 2 5 5 4 3 3 4 2 4 5 5 1 3
#> [1177] NA 2 5 2 4 3 3 2 4 5 4 5 3 3 3 1 2 4 5 3 2 4 1 4
#> [1201] 3 5 5 4 5 3 3 5 3 5 3 5 5 5 1 2 2 4 4 5 3 4 1 5
#> [1225] 3 2 1 1 3 5 5 5 4 2 4 4 2 2 NA 4 2 5 5 4 5 4 3 3
#> [1249] 2 4 3 3 3 3 3 3 2 NA 5 4 2 3 5 5 5 3 5 3 4 3 5 5
#> [1273] 5 2 5 4 4 4 4 NA 5 5 5 4 NA 4 4 5 NA 3 2 5 3 2 4 4
#> [1297] 3 5 4 5 4 5 5 5 2 4 2 3 4 4 4 2 5 3 3 4 4 4 NA 4
#> [1321] 3 5 3 5 NA 4 5 3 5 2 2 5 3 5 4 4 5 4 2 5 4 1 4 3
#> [1345] 4 3 2 2 4 1 4 5 5 4 5 4 1 2 5 5 3 4 4 4 4 5 3 1
#> [1369] 4 3 3 5 3 5 4 5 3 5 4 4 4 3 NA 5 3 4 3 1 5 5 3 3
#> [1393] 4 2 4 5 2 4 4 3 5 2 4 4 4 3 5 5 NA 5 4 2 2 2 4 4
#> [1417] 5 3 4 3 4 4 3 4 5 2 2 NA 4 5 1 5 5 3 5 5 5 4 4 5
#> [1441] 3 5 5 2 3 3 3 5 4 5 2 5 3 4 3 4 5 1 4 NA 4 3 5 4
#> [1465] 3 5 4 3 5 4 2 4 4 4 4 2 2 5 4 3 2 4 2 2 5 4 3 3
#> [1489] 5 4 4 2 4 2 5 5 3 2 4 4 4 4 1 4 2 4 4 4 4 2 2 4
#> [1513] 5 5 3 4 4 3 4 2 3 4 3 5 4 3 4 4 4 5 4 2 2 4 5 3
#> [1537] 3 3 3 4 3 2 5 1 3 3 3 3 5 1 3 3 5 4 1 4 4 3 2 3
#> [1561] 2 1 4 4 5 5 5 3 3 4 5 4 2 NA 5 4 5 2 3 2 3 4 5 3
#> [1585] 4 2 4 4 3 3 2 5 4 2 NA 2 4 4 4 3 2 4 4 3 3 3 4 2
#> [1609] 2 3 3 4 5 NA 5 2 3 4 3 4 3 4 5 2 4 5 3 3 5 4 5 5
#> [1633] 4 1 3 4 3 5 5 3 4 NA 4 4 4 2 5 2 4 3 2 4 3 3 4 4
#> [1657] 3 5 3 4 5 4 5 2 3 5 3 5 4 4 2 4 1 3 5 4 5 3 5 1
#> [1681] 4 5 3 4 4 2 2 5 3 5 5 5 5 4 2 4 3 3 3 2 5 4 1 4
#> [1705] 2 NA 5 4 4 3 2 4 3 4 5 4 4 3 5 4 4 5 5 2 3 NA 4 3
#> [1729] 2 1 3 3 2 4 NA 1 4 5 2 5 3 3 4 4 4 5 3 5 3 NA 5 3
#> [1753] 4 4 3 5 5 2 3 4 4 5 3 5 2 5 5 4 4 5 4 3 3 4 4 5
#> [1777] 3 4 1 5 5 4 4 4 2 4 5 4 4 4 4 5 4 5 NA 5 3 5 5 5
#> [1801] 5 3 5 3 4 NA 2 5 3 2 4 5 3 1 4 4 3 1 2 3 4 4 5 5
#> [1825] 5 2 4 4 5 1 5 3 4 3 4 3 4 3 5 4 5 3 2 5 NA 5 5 3
#> [1849] 4 2 5 1 4 5 4 2 3 3 3 3 3 3 4 4 NA 3 1 4 4 4 3 3
#> [1873] 3 4 4 5 5 3 4 NA 4 3 3 4 5 5 4 4 4 4 3 3 3 5 4 4
#> [1897] 3 2 4 4 4 4 2 4 1 5 2 5 3 5 NA 5 2 5 2 4 1 2 5 3
#> [1921] 4 3 2 3 2 4 4 5 4 5 4 4 5 5 4 2 5 5 4 2 2 5 5 4
#> [1945] 3 5 NA 2 3 4 3 2 4 5 1 4 4 4 5 3 5 5 4 2 2 3 2 4
#> [1969] 5 4 5 1 5 4 4 4 3 3 5 5 4 5 5 4 2 3 3 5 4 NA 5 5
#> [1993] 3 5 5 1 3 4 3 2 4 3 4 5 5 5 5 3 3 3 4 4 3 4 5 4
#> [2017] 5 3 2 3 5 4 4 5 4 3 4 4 5 3 2 4 5 2 4 NA 4 4 3 3
#> [2041] 4 3 4 4 3 3 3 3 5 3 1 3 3 1 2 4 3 3 5 2 5 3 1 3
#> [2065] 5 1 4 4 4 5 5 3 5 4 4 3 5 5 3 5 4 4 3 4 5 2 5 4
#> [2089] 4 4 3 3 4 1 4 3 1 3 3 5 4 4 5 2 3 1 5 4 3 5 1 4
#> [2113] 5 5 4 NA 1 5 5 4 4 2 5 4 3 4 3 3 3 4 3 3 5 3 3 5
#> [2137] 5 5 2 2 3 3 4 5 4 5 1 5 2 4 3 3 4 3 5 3 4 3 5 4
#> [2161] 2 5 3 5 4 5 2 3 5 5 5 3 4 2 5 4 4 5 1 5 NA 4 5 3
#> [2185] 2 4 4 4 3 2 5 4 3 4 4 4 5 2 NA 4 3 3 3 5 2 3 2 3
#> [2209] 4 3 4 5 NA 4 3 4 4 4 5 4 4 3 3 2 3 3 5 4 4 5 2 1
#> [2233] 5 4 2 1 3 3 4 5 4 5 2 5 5 5 4 3 4 2 3 4 4 5 4 5
#> [2257] 4 3 4 5 3 4 2 5 4 1 4 2 4 3 4 4 4 5 4 5 2 5 NA 4
#> [2281] 5 5 3 4 NA 5 3 5 1 3 2 4 5 5 5 2 4 3 1 3 3 5 3 3
#> [2305] 2 4 2 5 2 5 4 5 5 5 3 5 4 4 4 2 NA 2 NA 3 2 3 3 3
#> [2329] 4 4 5 2 4 3 1 2 3 3 2 4 1 4 NA 4 4 3 NA 3 2 5 4 5
#> [2353] 3 3 1 4 2 5 4 1 4 2 4 3 2 3 4 5 5 5 4 3 5 4 2 4
#> [2377] NA 1 5 5 1 1 4 3 4 5 3 2 5 4 3 4 4 3 4 4 3 4 5 3
#> [2401] 4 2 5 5 5 5 4 3 5 5 4 3 3 5 5 3 1 5 5 NA 5 5 4 4
#> [2425] 4 4 3 5 5 3 5 4 4 2 4 5 3 2 4 5 5 5 3 3 4 2 3 5
#> [2449] 3 4 NA 5 5 5 4 3 3 4 3 3 5 5 3 3 4 5 2 4 4 4 3 4
#> [2473] 5 3 4 2 4 5 3 3 3 3 5 3 5 3 2 5 4 4 NA 5 1 5 4 4
#> [2497] 2 4 2 4