Filter dataframe using multiple values

As the title says, I have a dataframe and I want to filter (keep) rows where the id variable is either 1 or 2.

An example:

using DataFrames

# eaxample data set
df1 = DataFrame(id = repeat(1:3, 3),
name = repeat(["bob", "jane", "steve"], inner = 3))


# filtering based on a single id - works fine 
kp_id = 1
df1[df1.id .== 1, :]

# filter on multipel id's - my attempt returns an empty dataframe
kp_id = (1,2)
df1[df1.id .== in(df1.id, kp_id), :]

Any advice would be much appreciated.

>Solution :

It comes down to writing a boolean expression that generates the desired BitVector. While you work on this, skip the indexing first and just work on

df1.id .== 1

Then a useful tool in julia is to consider the single case first:

julia> in(1, (1,2))
true
julia> in(3, (1,2))
false

so far so good! Lets broadcast this, but only on the first argument, so we protect the second argument with a Ref

julia> in.(df1.id, Ref((1,2)))
9-element BitVector:
 1
 1
 0
 1
 1
 0
 1
 1
 0

thus

df1[in.(df1.id, Ref(kp_id)), :]

will work.