How to delete all objects from my R environment except two that have different names

Question

Sometimes I have in my R environment tens of objects and I want to keep only one, two, or three of them. As an example:

df1   df8    dataframeX
df2   df9    ObjectY
df3   df10   df15
df4   df11   df16
df5   df12   dataframeZ
df6   df13
df7   df14

I found this useful script to retain one or several objects that follow the same name pattern:

rm(list = grep("^dataframe", ls(), value = TRUE, invert = TRUE))

dataframeX
dataframeZ

However, I don't know how to modify it to keep in my R environment objects which follow different name's patterns. For example, how could I keep the objects dataframeX , dataframeZ and `ObjectY?.

Does anyone know how to create a script that allows me to do that easily?

Answer 1

You may use

rm(list = grep("^(?:dataframe|Object)", ls(), value = TRUE, invert = TRUE))

See the regex demo

Details

• ^ - start of string
• (?: - start of a non-capturing group:
  • dataframe - a dataframe string
  • | - or
  • Object - an Object string
• ) - end of grouping.

The group is used to make sure the ^ is applied to both the alternatives, so that they were searched for at the start of a string only.