Amazon Redshift will no longer support the creation of new Python UDFs starting Patch 198. Existing Python UDFs will continue to function until June 30, 2026. For more information, see the [ blog post ](https://aws.amazon.com/blogs/big-data/amazon-redshift-python-user-defined-functions-will-reach-end-of-support-after-june-30-2026/). 

# DEXP function
<a name="r_DEXP"></a>

The DEXP function returns the exponential value in scientific notation for a double precision number. The only difference between the DEXP and EXP functions is that the parameter for DEXP must be a `DOUBLE PRECISION`. 

## Syntax
<a name="r_DEXP-synopsis"></a>

```
DEXP(number)
```

## Argument
<a name="r_DEXP-argument"></a>

 *number*   
The input parameter is a `DOUBLE PRECISION` number. 

## Return type
<a name="r_DEXP-return-type"></a>

`DOUBLE PRECISION`

## Example
<a name="r_DEXP-example"></a>

The following example uses the TICKIT sample database. For more information, see [Sample database](c_sampledb.md).

Use the DEXP function to forecast ticket sales based on a continuous growth pattern. In this example, the subquery returns the number of tickets sold in 2008. That result is multiplied by the result of the DEXP function, which specifies a continuous growth rate of 7% over 10 years. 

```
SELECT (SELECT SUM(qtysold) 
FROM sales, date
WHERE sales.dateid=date.dateid
AND year=2008) * DEXP((7::FLOAT/100)*10) qty2010;

+-------------------+
|      qty2010      |
+-------------------+
| 695447.4837722216 |
+-------------------+
```