R - levels are annoyingly messing things up, simple issue

Question

I have a variable in R that looks like so

> q
[1] 0.4231
Levels: 0.4231

I want to get rid of that crazy levels thing. I just want the value. How do I do this. I tried

> as.numeric(q)
[1] 1

Which doesn't work.

For example, I want to do some simple arithmetic, such as q+1, which I currently cannot do

> q+1
[1] NA
Warning message:
In Ops.factor(q, 1) : + not meaningful for factors

Answer 1

I think you have forgotten to do some simple steps. First, if you want to convert q to numeric, as.numeric(q) only returns q as if it is numeric, without converting q itself to numeric. Second, you cannot go directly from a factor to a numeric; you need to convert it to character, and then numeric.

This is what I tried below:

I reproduced your example:

q<-as.factor(0.423)
q
[1] 0.423
Levels: 0.423
as.numeric(q)
[1] 1
q+1
[1] NA
Warning message:
In Ops.factor(q, 1) : + not meaningful for factors

To show you that you cannot change a factor directly to numeric: see how q+1 is not eu

q<-as.numeric(q)
q+1
[1] 2

Finally, this is the correct way to convert a factor q to a numeric string:

q<-as.numeric(as.character((q)))
q+1
[1] 1.423