DescTools (version 0.99.14)

StrVal: Extract All Numeric Values From a String

Description

Extract all numeric values from a string, using a regular expression and return a list of the values. If there are several, the values can be either be pasted and/or casted from character vectors to numeric values.

Usage

StrVal(x, paste = FALSE, as.numeric = FALSE)

Arguments

x

a character vector

paste

should separatetly extracted numbers be pasted together? This can be useful to reverse a prior format action. Default is FALSE.

as.numeric

logical value, determining if the extracted values should be converted to a number or be returned as characters. Default is FALSE.

Value

• depending on the results the function will return either a character vector, in the case every element of x contained only one number, or a list of character vectors containing the found numbers.

See Also

other string functions, e.g. StrTrunc

Examples

# a simple vector with only one number per element
StrVal(x=c("week 1", "week 3", "week 4", "week 5"))

# several numbers per element, extract each part, do not paste and return characters
StrVal(x=c("This is 1. place: 45.2", "none", "12.1 but -2.7 follow, 10.2e23 "), 
       paste = FALSE, as.numeric = FALSE)

# a typical use case for this function is to reverse a previously 
#   applied number format

x <- c(100000, 4564654632, -456463)
xf <- Format(x, big.mark="'")

StrVal(xf, paste = TRUE, as.numeric = TRUE)

StrVal(xf, paste = TRUE, as.numeric = FALSE)
StrVal(xf, paste = FALSE, as.numeric = TRUE)
StrVal(xf, paste = FALSE, as.numeric = FALSE)