How to filter data in R?

Question

I have huge datasets that contain over a million rows and have some specific attributes. I need to filter data while maintaining other properties.

My data is as follows:

      ID   Prop1   Prop2   TotalProp
56891940     G02     G02           2
56892558     A61     G02           4
56892558     A61     A61           4
56892558     G02     A61           4
56892558     A61     A61           4
56892552     B61     B61           3
56892552     B61     B61           3
56892552     B61     A61           3
56892559     B61     G61           3
56892559     B61     B61           3
56892559     B61     B61           3 and so on more than million rows

What I need, I need to delete lines if all line IDs have 56891940 and 56892559, which have “prop1” and “prop2” the same, but not 56892558 and 56892559, because some lines are the same, but at least one of its properties different therefore I want to keep all values ​​from 56892558,56892552 and 56892559 and so on.

My end result should look like this:

      ID   Prop1   Prop2   TotalProp
56892558     A61     G02           4
56892558     A61     A61           4
56892558     G02     A61           4
56892558     A61     A61           4
56892552     B61     B61           3
56892552     B61     B61           3
56892552     B61     A61           3    
56892559     B61     G61           3
56892559     B61     C61           3
56892559     B61     B61           3

Answer 1

You can try

library(data.table)
setDT(df1)[, .SD[any(Prop1!=Prop2)], ID]
#          ID Prop1 Prop2 TotalProp
# 1: 56892558   A61   G02         4
# 2: 56892558   A61   A61         4
# 3: 56892558   G02   A61         4
# 4: 56892558   A61   A61         4
# 5: 56892552   B61   B61         3
# 6: 56892552   B61   B61         3
# 7: 56892552   B61   A61         3
# 8: 56892559   B61   G61         3
# 9: 56892559   B61   B61         3
#10: 56892559   B61   B61         3

Or as @Frank suggested

setDT(df1)[, if(any(Prop1!=Prop2)) .SD, ID]

dplyr

library(dplyr)
df1 %>%
    group_by(ID) %>%
    filter(any(Prop1!=Prop2))

ave base R

df1[with(df1, ave(Prop1!=Prop2, ID, FUN=any)),]