How can I rearrange my list?

Question

I have this list,
  {{a}, {i1, i2, i3}, {1, 2, 3}}

which I want to rearrange to this:
  {{1, i1, a}, {2, i2, a}, {3, i3, a}}

It is for use with ListPlot3D[]. How can I do it?

Charmbracelet · Accepted Answer

A crappy attempt:
{{a}, {i1, i2, i3}, {1, 2, 3}} /. {a_, b_, c_} :> 
   Thread[List[c, b, x]] /. x :> a

theorist · Answer

list = {{a}, {i1, i2, i3}, {1, 2, 3}} 
#~Join~First@list& /@Thread@Reverse@Rest@list

user1066 · Answer

Thread[{#3,#2,Sequence@@#1}]&@@lst

{{1, i1, a}, {2, i2, a}, {3, i3, a}}

Slightly shorter
Thread[{#3,#2,First@#1}]&@@lst

kglr · Answer

f = Thread @ Reverse @ PadRight[#, Automatic, #] &;

Examples:
lst1 = {{a}, {i1, i2, i3}, {1, 2, 3}};

f @ lst1

{{1, i1, a}, {2, i2, a}, {3, i3, a}}

lst2 = {{a}, {i1, i2, i3}, {x, y}, {1, 2, 3, 4}};

f @ lst2

{{1, x, i1, a}, {2, y, i2, a}, {3, x, i3, a}, {4, y, i1, a}}

4 Answers