# IsLower

| **Name**    | ***IsLower***                                                                                                                                                                                              |
| ----------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Syntax      | IsLower (String str)                                                                                                                                                                                       |
| Purpose     | To check whether the specified character within a string, in the specified index position, is lowercase alphabetic.                                                                                        |
| Description | Checks whether specified character is lowercase alphabetic.                                                                                                                                                |
| Return Type | Boolean                                                                                                                                                                                                    |
| Parameters  | <p>str \[System.String] – String containing the character to test</p><p>index \[System.Int32] – Numerical position of the character in the string to test. If not specified, index is presumed to be 0</p> |

![](https://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/0%20\(67\).png)

**Example**

In this example, we are passing the required parameters to the function transformation object using a *Variables* object.

Where,

*str* = aAbBcC

*index* = 0

![](https://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/1%20\(68\).png)

Right-click on the function transformation object and select *Preview Output.* You can see that Astera Data Stack has returned “True”, as the character in the specified numerical position is a lowercase alphabet.

![](https://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/2%20\(68\).png)

Conversely, if we replace the *index* value with “1”, the output value will return the Boolean value, “False”, as shown below:

![](https://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/3%20\(23\).png)


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