Computes the square root of the input parameter. Input value can be a Decimal or Integer literal or a reference to a column containing numeric values. All generated values are non-negative.
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
Numeric literal example:
sqrt(25)
Output: Returns the square root of 25, which is 5.
Column reference example:
sqrt(MyValue)
Output: Returns the square root of the values of the MyValue column.
Syntax and Arguments
sqrt(numeric_value)
| Argument | Required? | Data Type | Description |
|---|---|---|---|
| numeric_value | Y | string, decimal, or integer | Name of column or Decimal or Integer literal to apply to the function |
For more information on syntax standards, see Language Documentation Syntax Notes.
numeric_value
Name of the column or numeric literal whose values are used to compute the square root.
NOTE: Negative input values generate null output values.
- Missing input values generate missing results.
- Literal numeric values should not be quoted.
- Multiple columns and wildcards are not supported.
Usage Notes:
| Required? | Data Type | Example Value |
|---|---|---|
| Yes | String (column reference) or Integer or Decimal literal | 25 |
Tip: For additional examples, see Common Tasks.
Examples
Example - Pythagorean Theorem
POW and SQRT functions work together to compute the hypotenuse of a right triangle using the Pythagorean theorem.POW- X Y . In this case, 10 to the power of the previous one. See POW Function .SQRT- computes the square root of the input value. See SQRT Function.
The Pythagorean theorem states that in a right triangle the length of each side (x,y) and of the hypotenuse (z) can be represented as the following:
z2 = x 2 + y 2
Therefore, the length of z can be expressed as the following:
z = sqrt(x 2 + y 2 )
Source:
The dataset below contains values for x and y:
| X | Y |
|---|---|
| 3 | 4 |
| 4 | 9 |
| 8 | 10 |
| 30 | 40 |
Transformation:
You can use the following transformation to generate values for z2.
NOTE: Do not add this step to your recipe right now.
| Transformation Name | New formula |
|---|---|
| Parameter: Formula type | Single row formula |
| Parameter: Formula | (POW(x,2) + POW(y,2)) |
| Parameter: New column name | 'Z' |
You can see how column Z is generated as the sum of squares of the other two columns, which yields z2.
Now, edit the transformation to wrap the value computation in a SQRT function. This step is done to compute the value for z, which is the distance between the two points based on the Pythagorean theorem.
| Transformation Name | New formula |
|---|---|
| Parameter: Formula type | Single row formula |
| Parameter: Formula | SQRT((POW(x,2) + POW(y,2))) |
| Parameter: New column name | 'Z' |
Results:
| X | Y | Z |
|---|---|---|
| 3 | 4 | 5 |
| 4 | 9 | 9.848857801796104 |
| 8 | 10 | 12.806248474865697 |
| 30 | 40 | 50 |
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