[R] add specific fields in for loop

Bert Gunter
2022-11-15T17:08:43Z

There is no function columns() in base R.
Is 'date' an object that contains column names or indices? Or do you
mean
that it is a string that appears in the column names you wish to loop over?

A small reprex should be easy to provide to show us explicitly what you
want. Please do so -- unless, of course, someone with greater insight than
I provides you a satisfactory answer.

Cheers,
Bert

On Tue, Nov 15, 2022 at 8:19 AM Kai Yang via R-help <r-help at
r-project.org>
wrote:

> Hi Team,
> I can write a for loop like this:
> for (i in columns(df)){
>   ......
> }
>
> But it will working on all column in dataframe df. If I want to work on
> some of specific fields (say: the fields' name content 'date'),
how should
> I modify the for loop? I changed the code below, but it doesn't work.
> for (i in columns(df) %in% 'date' ){
>   .....
> }
>
>
> Thank you,
> Kai
>
>         [[alternative HTML version deleted]]
>
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