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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)


ArgumentRequired?Data TypeDescription
numeric_valueYstring, decimal, or integerName 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 TypeExample Value
YesString (column reference) or Integer or Decimal literal25

Examples

Tip: For additional examples, see Common Tasks.

Example - Pythagorean Theorem

The following example demonstrates how the 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:

 

XY
34
49
810
3040

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:

XYZ
345
499.848857801796104
81012.806248474865697
304050

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