Recoding mutilple columns in 1 shot

[Lopa2016]

Hi ,

I want to recode multiple fields for e.g. gender,marital status ,education to numeric for eg. male=1 ,female=2 & so on

convert <-function(x,y,z)
{
if(x$y==z)
{x$y=as.factor(1)}

else{
x$y=as.factor(2)
}

}
train$Gender<-convert(train,Gender,"Male")

But this throws an error { : argument is of length zero which I believe is because the gender column is character. Can some one help out?

Thanks in advance.

[Frank]

The function has a few issues:

• It needs to return something at the end (probably x). See ?return.
• We cannot write x$y programmatically passing y, unfortunately. Instead x[[y]] <- should work where y is a string column name with quotes.
• if and else are for control flow (determining which pieces of code get run), while you you want this to apply in a vectorized way to each element of x$y.

I'd suggest approaching this with a lookup table and a left join. The tidyverse way is shown here:

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