EXAMPLE - Nest Columns into Arrays

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This section provides simple examples of nesting columns into Arrays by extracting values from a column or nesting one or more columns into an Array column.

Create by extraction:

You can create an array of values by extracting pattern-based values from a specified column. The following transformation extracts from the msg column a list of all values where all letters are capitalized and places them into the new acronyms column:

Transformation Name	`Extract matches into Array`
Parameter: Column	`msg`
Parameter: Pattern matching elements in the list	`{upper}+`
Parameter: New column name	`acronyms`

msg	acronyms
SCUBA, IMHO, is the greatest sport in the world.	["SCUBA","IMHO"]
	[]
LOL, that assignment you finished is DOA. You need to fix it PDQ.	["LOL","DOA","Y","PDQ"]

Notes:

An empty input column value renders an empty array.
In the final row, the Pattern matches on the "Y" value. To fix this, you can change the Pattern matching value to the following, which matches on two or more uppercase letters in a row:
```
`{upper}{upper}+`
```

Create by nesting:

You can create arrays by nesting together the values from multiple columns:

num1	num2	num3
11	12	13
14	15	16
17	18	19

You can nest the values in num1 and num2 into a single array and then to nest the array with num3:

NOTE: If you are nesting a multi-level array, you should nest from the lowest level to the top level.

Transformation Name	`Nest columns into Objects`
Parameter: Columns1	`num1`
Parameter: Columns2	`num2`
Parameter: Nest columns to	`Array`
Parameter: New column name	`nest1`

Then, you can perform the nesting of the top-level elements:

NOTE: The order in which you list the columns to nest determines the order in which the elements appear in the generated array.

Transformation Name	`Nest columns into Objects`
Parameter: Columns1	`nest1`
Parameter: Columns2	`num3`
Parameter: Nest columns to	`Array`
Parameter: New column name	`nest2`

In the generated columns, you notice that all values are quoted, even though these values are integers.

NOTE: Elements that are generated into arrays using a nest transformation are always rendered as quoted values.

You can use the following transformation to remove the quotes from the nest2 column:

Transformation Name	`Replace text or patterns`
Parameter: Column	`nest2`
Parameter: Find	`'"'`
Parameter: Replace	`(empty)`
Parameter: Match all occurrences	`true`

num1	num2	num3	nest2
11	12	13	[[11,12],13]
14	15	16	[[14,15],16]
17	18	19	[[17,18],19]

See Also for EXAMPLE - Nest Columns into Arrays:

Page:

Array Data Type
Page:

ARRAYZIP Function
Page:

EXAMPLE - Flatten an Array
Page:

EXAMPLE - Unnest an Array
Page:

Working with Arrays
Page:

EXAMPLE - LIST Math Functions
Page:

EXAMPLE - ARRAYINDEXOF and ARRAYRIGHTINDEXOF Functions
Page:

ARRAYCONCAT Function
Page:

ARRAYCROSS Function
Page:

ARRAYELEMENTAT Function

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EXAMPLE - Nest Columns into Arrays