> ## Documentation Index
> Fetch the complete documentation index at: https://fuse-docs.swovo.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Float Columns

> How to add a float column to your importer through code.

You can add a column to your importer directly through the UI of your Fuse account, or you can do so in code using the documentation below.

The Float column type can accept whole integers and decimals. It supports functionalities such as:

* Validate that input is greater than or less than a certain number
* Round values to the nearest integer

## addColumn Function

The `addColumn` function accepts an object as an argument.

* `internal_key` (String) - required: The internal key used to access a column's value.
* `label` (String) - required: The user-facing column label that is shown in the interface.
* `column_type` (String) - required: Should be "float".
* `required` (String) - required: Whether or not the column is required.
* `position` (Optional): The position or order of the column.
* `unique` (Optional): Whether values should be unique.
* `validations` (Optional): An array of built-in data validations. See [Built-in Float Validations](#built-in-float-validations).
* `transformations` (Optional): An array of built-in data transformations. See [Built-in Float Transformations](#built-in-float-transformations).

### Example Code

<Tabs>
  <Tab title="JavaScript">
    ```javascript theme={null}
      const importer = new FuseImporter();

      importer.getSessionToken = ... // see https://fuse-docs.flatirons.com/getting-started/sessions


      const validations = [
        {
          validation_type: "less_than",
          message: "Must be less than 10",
          options: {
            less_than: 10,
          },
        },
      ];

      const transformations = [
        {
          validation_type: "number_of_decimals",
        },
      ];

      importer.addColumn({
        internal_key: "age",
        label: "Age",
        column_type: "float",
        required: true,
        position: 1,
        validations: validations,
        transformations: transformations,
      });

      importer.show();

    ```
  </Tab>

  <Tab title="TypeScript">
    ```typescript theme={null}
      const importer = new FuseImporter();

      importer.getSessionToken = ... // see https://fuse-docs.flatirons.com/getting-started/sessions

      // ColumnValidations should be imported from "fuse-importer"
      const validations: ColumnValidations<"float">[] = [
        {
          validation_type: "less_than",
          message: "Must be less than 10",
          options: {
            less_than: 10,
          },
        },
      ];

      // ColumnTransformations should be imported from "fuse-importer"
      const transformations: ColumnTransformations<"float">[] = [
        {
          validation_type: "number_of_decimals",
        },
      ];

      importer.addColumn({
        internal_key: "age",
        label: "Age",
        column_type: "float",
        required: true,
        position: 1,
        validations: validations,
        transformations: transformations,
      });

      importer.show();
    ```
  </Tab>
</Tabs>

## Built-in Float Validations

The `addColumn` object accepts an array of validations. Each validation has three properties:

* `validation_type:` the name of the validation
* `message:` the message showed to the end user if the validation fails
* `options:` options for the specific validation type

The validations property accepts an array of objects that contains these possible values: `validation_type`, `message` and `options`. As the example below:

```javascript theme={null}
validations: [
  {
    validation_type: "less_than",
    message: "Must be less than 10",
    options: {
      less_than: 10,
    },
  },
];
```

### less\_than

Specifies that the value must be less than a certain number.

```javascript theme={null}
validations: [
  {
    validation_type: "less_than",
    message: "Must be less than 10",
    options: {
      less_than: 10,
    },
  },
];
```

### greater\_than

Specifies that the value must be greater than a certain number.

```javascript theme={null}
validations: [
  {
    validation_type: "greater_than",
    message: "Must be greater than 10",
    options: {
      greater_than: 10,
    },
  },
];
```

### even

Specifies that the value must be even.

```javascript theme={null}
validations: [
  {
    validation_type: "even",
    message: "Must be an even number",
  },
];
```

### odd

Specifies that the value must be odd.

```javascript theme={null}
validations: [
  {
    validation_type: "odd",
    message: "Must be an odd number",
  },
];
```

### regex

Specifies that the value must match a regex

```javascript theme={null}
validations: [
  {
    validation_type: "regex",
    message: "Must not have a leading zero",
    options: {
      pattern: /^([+-]?[1-9]\d*|0)$/,
    },
  },
];
```

## Built-in Float Transformations

The options property of `addColumn` accepts an array of transformations. Each transformation has two possible properties:

* `transformation_type:` the name of the transformation
* `options:` options for the specific transformation type

The transformations property accepts an array of objects that contains these possible values: `transformation_type` and `options`. As the example below:

```javascript theme={null}
transformations: [
  {
    transformation_type: "number_of_decimals",
    options: {
      number_of_decimals: 2,
    },
  },
];
```

### number\_of\_decimals

This transformation allows you to specify the desired number of decimal places for the float values in the column. For example, if the original value is 3.14159 and you specify 2 decimal places, it becomes 3.14. You should pass an `options` object to the transformation object with a `number_of_decimals` integer value in your desired format.

```javascript theme={null}
transformations: [
  {
    transformation_type: "number_of_decimals",
    options: {
      number_of_decimals: 2,
    },
  },
];
```