how to remove factors from whole dataframe?

Hi Luigi,
Okay, so you mean:
I want to change all factors in a dataframe to character class, _not_
remove them.

factor2character<-function(x) if(is.factor(x)) return(as.character(x))
else return(x)
df1<-lapply(df,factor2character)

Jim

On Sun, Sep 19, 2021 at 8:03 PM Luigi Marongiu <marongiu.luigi at gmail.com> wrote:

Thank you Jim, but I obtain:
```

str(df)

'data.frame': 5 obs. of  3 variables:
 $ region : Factor w/ 5 levels "A","B","C","D",..: 1 2 3 4 5
 $ sales  : num  13 16 22 27 34
 $ country: Factor w/ 5 levels "a","b","c","d",..: 1 2 3 4 5

df1<-df[,!unlist(lapply(df,is.factor))]
str(df1)

 num [1:5] 13 16 22 27 34

df1

[1] 13 16 22 27 34
```
I was expecting
```
str(df)
'data.frame': 5 obs. of  3 variables:
 $ region : char "A","B","C","D",..: 1 2 3 4 5
 $ sales  : num  13 16 22 27 34
 $ country: char "a","b","c","d",..: 1 2 3 4 5
```

On Sun, Sep 19, 2021 at 11:37 AM Jim Lemon <drjimlemon at gmail.com> wrote:

Hi Luigi,
It's easy:

df1<-df[,!unlist(lapply(df,is.factor))]

_except_ when there is only one column left, as in your example. In
that case, you will have to coerce the resulting vector back into a
one column data frame.

Jim

On Sun, Sep 19, 2021 at 6:18 PM Luigi Marongiu <marongiu.luigi at gmail.com> wrote:

Hello,
I woul dlike to remove factors from all the columns of a dataframe.
I can do it n a column at the time with
```

df <- data.frame(region=factor(c('A', 'B', 'C', 'D', 'E')),
                 sales = c(13, 16, 22, 27, 34), country=factor(c('a',
'b', 'c', 'd', 'e')))

new_df$region <- droplevels(new_df$region)
```

What is the syntax to remove all factors at once (from all columns)?
For this does not work:
```

str(df)

'data.frame': 5 obs. of  3 variables:
 $ region : Factor w/ 5 levels "A","B","C","D",..: 1 2 3 4 5
 $ sales  : num  13 16 22 27 34
 $ country: Factor w/ 5 levels "a","b","c","d",..: 1 2 3 4 5

df = droplevels(df)
str(df)

'data.frame': 5 obs. of  3 variables:
 $ region : Factor w/ 5 levels "A","B","C","D",..: 1 2 3 4 5
 $ sales  : num  13 16 22 27 34
 $ country: Factor w/ 5 levels "a","b","c","d",..: 1 2 3 4 5
```
Thank you

--
Best regards,
Luigi