[R] Removing variables from data frame with a wile card

[Jeff Newmiller]

Complain, complain...

x[ names( x ) != "V2" ]

or

x[ ! names( x ) %in% c( "V2", "V3" ) ]

or any other character or logical or integer expression that selects columns you want...

On February 12, 2023 6:38:00 PM PST, Steven Yen <styen using ntu.edu.tw> wrote:
>x[“V2”] would retain columns of x headed by V2. What I need is the opposite——I need a data grime with those columns excluded.
>
>Steven from iPhone
>
>> On Feb 13, 2023, at 9:33 AM, Rolf Turner <r.turner using auckland.ac.nz> wrote:
>> 
>> 
>>> On Sun, 12 Feb 2023 14:57:36 -0800
>>> Jeff Newmiller <jdnewmil using dcn.davis.ca.us> wrote:
>>> 
>>> x["V2"]
>>> 
>>> is more efficient than using drop=FALSE, and perfectly normal syntax
>>> (data frames are lists of columns).
>> 
>> <SNIP>
>> 
>> I never cease to be amazed by the sagacity and perspicacity of the
>> designers of R.  I  would have worried that x["V2"] would turn out to be
>> a *list* (of length 1), but no, it retains the data.frame class, which
>> is clearly the Right Thing To Do.
>> 
>> cheers,
>> 
>> Rolf
>> 
>> -- 
>> Honorary Research Fellow
>> Department of Statistics
>> University of Auckland
>> Stats. Dep't. phone: +64-9-373-7599 ext. 89622
>> Home phone: +64-9-480-4619
>> 

-- 
Sent from my phone. Please excuse my brevity.