R help - Aug 2021 - Apply gsub to dataframe to modify row values

Hello,
I have a dataframe where I would like to change the string of certain
rows, essentially I am looking to remove some useless text from the
variables.
I tried with:
```
> df = data.frame(VAR = 1:3, VAL = c("value is blue", "Value
is red", "empty"))
> df[df$VAL] = gsub("value is ", "", df$VAL, ignore.case
= TRUE, perl = FALSE)
> df
  VAR           VAL value is blue Value is red empty
1   1 value is blue          blue         blue  blue
2   2  Value is red           red          red   red
3   3         empty         empty        empty empty
```
which is of course wrong because I was expecting
```
  VAR           VAL
1   1             blue
2   2             red
3   3            empty
```
What is the correct syntax in these cases?
Thank you

Hi Luigi,
Ah, now I see:

 df$VAL<-gsub("Value is","",df$VAL,ignore.case=TRUE)
df
 VAR   VAL
1   1  blue
2   2   red
3   3 empty

Jim

On Mon, Aug 9, 2021 at 6:43 PM Luigi Marongiu <marongiu.luigi at
gmail.com> wrote:
>
> Hello,
> I have a dataframe where I would like to change the string of certain
> rows, essentially I am looking to remove some useless text from the
> variables.
> I tried with:
> ```
> > df = data.frame(VAR = 1:3, VAL = c("value is blue",
"Value is red", "empty"))
> > df[df$VAL] = gsub("value is ", "", df$VAL,
ignore.case = TRUE, perl = FALSE)
> > df
>   VAR           VAL value is blue Value is red empty
> 1   1 value is blue          blue         blue  blue
> 2   2  Value is red           red          red   red
> 3   3         empty         empty        empty empty
> ```
> which is of course wrong because I was expecting
> ```
>   VAR           VAL
> 1   1             blue
> 2   2             red
> 3   3            empty
> ```
> What is the correct syntax in these cases?
> Thank you
>
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