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# calculate-column

## Description

<mark style="color:purple;">`calculate-column`</mark> *adaptor applies one of the following mathematical operations using values in two columns in a datatable*:

* `add`: Adds values in left column to values in right column (left + right).
* `subtract`: Subtract values in right column from values in left column (left - right).
* `multiply`: Multiplies values in left column by values in right column (left \* right).
* `divide`: Divides values in left column by values in right column (left / right).
* `percent`: Calculates the percentage ratio of values in left column out of values in right column (left / right \* 100).
* `exponent`: Calculates values in left column (raised) to the (power of) of values in right column (left \*\* right).

## Inputs

**`data`**\
Type: `datatable`\
Required: Yes\
The datatable containing the column to be formatted.

**`left column`**\
Type: `text`\
Required: Yes\
The name of the column containing the values on the left-hand side of the operator.

**`right column`**\
Type: `text`\
Required: Yes\
The name of the column containing the values on the right-hand side of the operator.

**`operation`**\
Type: `text`\
Required: No\
The calculate operation to be used. Can be either `add`, `subtract`, `multiply`, `divide`, `percent`, or `exponent`. If unspecified, defaults to `add`.

**`result column`**\
Type: `text`\
Required: No\
The name of the column to which the calculated values will be added.

**`result unit`**\
Type: `text`\
Required: No\
An optional unit to be appended to the result. If unspecified, defaults to blank.

## Outputs

**`data`**\
Type: `datatable`\
A datatable with formatted values.

## Examples

### Example 1: Default behaviour.

#### Inputs:

`data`:

<table><thead><tr><th width="134.5">Location</th><th width="186">January case count</th><th width="195">February case count</th></tr></thead><tbody><tr><td>County X</td><td>27</td><td>15</td></tr><tr><td>County Y</td><td>58</td><td>80</td></tr></tbody></table>

`left column`: January case count

`right column`: February case count

#### Outputs:

* `data`:

<table><thead><tr><th width="134.5">Location</th><th width="186">January case count</th><th width="195">February case count</th><th>result</th></tr></thead><tbody><tr><td>County X</td><td>27</td><td>15</td><td>42</td></tr><tr><td>County Y</td><td>58</td><td>80</td><td>138</td></tr></tbody></table>

-> Added the values in `January case count` column to the values in `February case count` column. Results were displayed in a new column.

### Example 2: Calculate percentage column.

#### Inputs:

`data`:

<table><thead><tr><th width="134.5">Month</th><th width="126">Sales</th><th width="127">Total</th></tr></thead><tbody><tr><td>Jan</td><td>1458</td><td>14580</td></tr><tr><td>Feb</td><td>5832</td><td>14580</td></tr></tbody></table>

`left column`: Sales

`right column`: Total

`result column`: Percentage

`result unit`: %

#### Outputs:

* `data`:

  <table><thead><tr><th width="149">Month</th><th>Sales</th><th>Total</th><th>Percentage</th></tr></thead><tbody><tr><td>Jan</td><td>1458</td><td>14580</td><td>10%</td></tr><tr><td>Feb</td><td>5832</td><td>14580</td><td>40%</td></tr></tbody></table>

-> Calculated the percentage ratio of values in `Sales` column out of values in `Total` column. The result was added to the `Percentage` column.