POW Function
Computes the value of the first argument raised to the value of the second argument.
Each argument can be a Decimal or Integer literal or a reference to a column containing numeric values.
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:
pow(10,3)
Output: Returns the value of 103, which is 1000
.
Column reference example:
pow(MyValue,2)
Output: Returns the value of the MyValue
column raised to the power of 2 (squared).
Syntax and Arguments
pow(base_numeric_value, exp_numeric_value)
Argument | Required? | Data Type | Description |
---|---|---|---|
base_numeric_value | Y | string, decimal, or integer | Name of column or Decimal or Integer literal that is the base value to be raised to the power of the second argument |
exp_numeric_value | Y | string, decimal, or integer | Name of column or Decimal or Integer literal that is the power to which to raise the base value |
For more information on syntax standards, see Language Documentation Syntax Notes.
base_numeric_value
Name of the column or numeric literal whose values are used as the bases for the exponential computation.
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 | 2.3 |
exp_numeric_value
Name of the column or numeric literal whose values are used as the power to which the base-numeric value is raised.
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 | 5 |
Examples
提示
For additional examples, see Common Tasks.
Example - Exponential functions
This example demonstrates the exponential functions.
Functions:
Item | Description |
---|---|
EXP Function | Computes the value of e raised to the specified power. The value can be a Decimal or Integer literal or a reference to a column containing numeric values. |
LN Function | Computes the natural logarithm of an input value. The value can be a Decimal or Integer literal or a reference to a column containing numeric values. |
LOG Function | Computes the logarithm of the first argument with a base of the second argument. |
POW Function | Computes the value of the first argument raised to the value of the second argument. |
Source:
rowNum | X |
---|---|
1 | -2 |
2 | 1 |
3 | 0 |
4 | 1 |
5 | 2 |
6 | 3 |
7 | 4 |
8 | 5 |
Transformation:
Transformation Name | |
---|---|
Parameter: Formula type | Single row formula |
Parameter: Formula | EXP (X) |
Parameter: New column name | 'expX' |
Transformation Name | |
---|---|
Parameter: Formula type | Single row formula |
Parameter: Formula | LN (expX) |
Parameter: New column name | 'ln_expX' |
Transformation Name | |
---|---|
Parameter: Formula type | Single row formula |
Parameter: Formula | LOG (X) |
Parameter: New column name | 'logX' |
Transformation Name | |
---|---|
Parameter: Formula type | Single row formula |
Parameter: Formula | POW (10,logX) |
Parameter: New column name | 'pow_logX' |
Results:
In the following, (null value)
indicates that a null value is generated for the computation.
rowNum | X | expX | ln_expX | logX | pow_logX |
---|---|---|---|---|---|
1 | -2 | 0.1353352832366127 | -2 | (null value) | (null value) |
2 | -1 | 0.1353352832366127 | -0.9999999999999998 | (null value) | (null value) |
3 | 0 | 1 | 0 | (null value) | 0 |
4 | 1 | 2.718281828459045 | 1 | 0 | 1 |
5 | 2 | 7.3890560989306495 | 2 | 0.30102999566398114 | 1.9999999999999998 |
6 | 3 | 20.085536923187668 | 3 | 0.47712125471966244 | 3 |
7 | 4 | 54.59815003314423 | 4 | 0.6020599913279623 | 3.999999999999999 |
8 | 5 | 148.41315910257657 | 5 | 0.6989700043360187 | 4.999999999999999 |
Example - Pythagorean Theorem
In this example, you learn how to compute exponentials and square roots on your numeric data.
Functions:
Item | Description |
---|---|
POW Function | Computes the value of the first argument raised to the value of the second argument. |
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. |
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.
注意
Do not add this step to your recipe right now.
Transformation Name | |
---|---|
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 | |
---|---|
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 |