kutils (version 1.73)

assignRecode: A variable is transformed in an indicated way

Description

In the variable key framework, the user might request transformations such as the logarithm, exponential, or square root. This is done by including strings in the recodes column, such as "log(x + 1)" or "3 + 1.1 * x + 0.5 * x ^ 2". This function implements the user's request by parsing the character string and applying the indicated re-calculation.

Usage

assignRecode(x, recode = NULL)

Value

A new column

Arguments

x

A column to be recoded

recode

A character string using placeholder "x". See examples

Author

Paul Johnson <[e-mail]>

Details

In the variable key framework, this is applied to the raw data, after missings are imposed.

Examples

set.seed(234234)
x <- rpois(100, lambda = 3)
x <- x[order(x)]
str1 <- "log(x + 1)"
xlog <- assignRecode(x, recode = str1)
plot(xlog ~ x, type = "l")
mean(xlog, na.rm = TRUE)
str2 <- "x^2"
xsq <- assignRecode(x, recode = str2)
plot(xsq ~ x, type = "l")
str3 <- "sqrt(x)"
xsrt <- assignRecode(x, recode = str3)