ARRAYSORT Function
Sorts array values in the specified column, array literal, or function that returns an array in ascending or descending order.
This function calculates based on the outer layer of an array. If your array is nested, the sorting of inner elements is not factored.
Wrangle vs. SQL: This function is part of Wrangle, a proprietary data transformation language. Wrangle is not SQL. For more information, see Wrangle Language.
Basic Usage
Array literal reference example:
arraysort([A,B,C,D],descending)
Output: Returns the following array: [D,C,B,A].
Column reference example:
arraysort(myArrays,ascending)
Output: Returns the arrays listed in the myArrays column sorted in ascending order.
Syntax and Arguments
arraysort(array_ref,order_enum)
Argument | Required? | Data Type | Description |
|---|---|---|---|
array_ref | Y | string | Name of Array column, Array literal, or function returning an Array to apply to the function |
order_enum | Y | string (enumerated value) | Order is defined as either:
|
For more information on syntax standards, see Language Documentation Syntax Notes.
array_ref
Name of the array column, array literal, or function returning an array whose array values you wish to sort.
Multiple columns and wildcards are not supported.
Usage Notes:
Required? | Data Type | Example Value |
|---|---|---|
Yes | String (column reference or function) or array literal | myArray1 |
order_enum
String literal indicating the order by which the referenced arrays should be sorted:
ascending- (default) lowest values for the valid data type are listed first.descending- Null/empty values are sorted first, followed by mismatched values. Then, the array values that are valid for the specified data type are listed in descending order.
Usage Notes:
Required? | Data Type | Example Value |
|---|---|---|
No | String (enumerated value) | descending |
Examples
Astuce
For additional examples, see Common Tasks.
Example - Student progress across tests
This example illustrates how to return n-based number of elements in an array.
Functions:
Item | Description |
|---|---|
ARRAYLEN Function | Computes the number of elements in the arrays in the specified column, array literal, or function that returns an array. |
ARRAYELEMENTAT Function | Computes the 0-based index value for an array element in the specified column, array literal, or function that returns an array. |
ARRAYSORT Function | Sorts array values in the specified column, array literal, or function that returns an array in ascending or descending order. |
Source:
Here are some student test scores. Individual scores are stored in the Scores column. You want to:
Flag the students who have not taken four tests.
Compute the range in scores for each student.
LastName | FirstName | Scores |
|---|---|---|
Allen | Amanda | [79, 83,87,81] |
Bell | Bobby | [85, 92, 94, 98] |
Charles | Cameron | [88,81,85] |
Dudley | Danny | [82,88,81,77] |
Ellis | Evan | [91,93,87,93] |
Transformation:
First, you want to flag the students who did not take all four tests:
Transformation Name | |
|---|---|
Parameter: Formula type | Single row formula |
Parameter: Formula | IF(ARRAYLEN(Scores) < 4,"incomplete","") |
Parameter: New column name | 'Error' |
This test flags Cameron Charles only.
The following transform sorts the array values in highest to lowest score:
Transformation Name | |
|---|---|
Parameter: Columns | Scores |
Parameter: Formula | ARRAYSORT(Scores, 'descending') |
The following transforms extracts the first (highest) and last (lowest) value in each student's test scores, provided that they took four tests:
Transformation Name | |
|---|---|
Parameter: Formula type | Single row formula |
Parameter: Formula | ARRAYELEMENTAT(Scores,0) |
Parameter: New column name | 'highestScore' |
Transformation Name | |
|---|---|
Parameter: Formula type | Single row formula |
Parameter: Formula | ARRAYELEMENTAT(Scores,3) |
Parameter: New column name | 'lowestScore' |
Astuce
You could also generate the Error column when the Scores4 column contains a null value. If no value exists in the array for the ARRAYELEMENTAT function, a null value is returned, which would indicate in this case an insufficient number of elements (test scores).
You can now track change in test scores:
Transformation Name | |
|---|---|
Parameter: Formula type | Single row formula |
Parameter: Formula | SUBTRACT(highestScore,lowestScore) |
Parameter: New column name | 'Score_range' |
Results:
LastName | FirstName | Scores | Error | lowestScore | highestScore | Score_range |
|---|---|---|---|---|---|---|
Allen | Amanda | [87,83,81,79] | 79 | 87 | 8 | |
Bell | Bobby | [98,94,92,85] | 85 | 98 | 13 | |
Charles | Cameron | [88,85,81] | incomplete | 88 | ||
Dudley | Danny | [88,82,81,77] | 77 | 88 | 11 | |
Ellis | Evan | [93,93,91,87] | 87 | 93 | 6 |