SQRT Function

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.

Basic Usage

Numeric literal example:

derive type:single value:SQRT(25 )

Output: Generates a column containing the square root of 25, which is 5.

Column reference example:

derive type:single value:SQRT(MyValue) as: 'sqroot_MyValue'

Output: Generates the new sqroot_myValue column containing the square root of the values of the MyValue column.

Syntax

derive type:single value: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

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

Transform:

You can use the following transform to generate values for z2.

NOTE: Do not add this step to your recipe right now.

derive type:single value:(POW(x,2) + POW(y,2)) as:'Z'

You can see how column Z is generated as the sum of squares of the other two columns. Now, wrap the value computation in a SQRT function:

derive type:single value:SQRT((POW(x,2) + POW(y,2))) as: 'Z'

Results:

XYZ
345
499.848857801796104
81012.806248474865697
304050

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