Get / Array Layer

Extract element at specified index from each fixed-length array. Similar to array[i] indexing in Python or nth() in R. Supports both positive and negative indexing.

Example transformation (arrays of length 3):

Positive indexing (index=1):

arrays	element
[1, 2, 3]	2
[x, y, z]	y

Negative indexing (index=-1):

arrays	element
[1, 2, 3]	3
[x, y, z]	z

Common applications:

Accessing specific positions
Extracting last elements (negative index)
Sequential data access
Pattern extraction

Note: All arrays must have the same fixed length. Positive indices count from start (0-based), negative indices count from end (-1 is last element).

Table

Select

column

The fixed-length array column to access. All arrays must have same length:

Numeric arrays: [1, 2, 3]
String arrays: [x, y, z]
Boolean arrays: [true, false, true]
Date/time arrays: [2024-01-01, 2024-01-02, 2024-01-03]

Index

oneof

Fixed

i32

Index of the element to extract. Supports both positive and negative indices: For arrays of length N: Positive (from start):

0 to N-1 (e.g., 0, 1, 2 for length 3) Negative (from end):
-1 to -N (e.g., -1, -2, -3 for length 3)

SelectIdx

column

Select using this column containing indices.

Name for the new column. If not provided, the system generates a unique name. If AsColumn matches an existing column, the existing column is replaced. The name should follow valid column naming conventions.