% This is generated by ESQL's AbstractFunctionTestCase. Do no edit it. See ../README.md for how to regenerate it.

**Example**

```esql
ROW str1 = "5.20128E11", str2 = "foo"
| EVAL dbl = TO_DOUBLE("520128000000"), dbl1 = TO_DOUBLE(str1), dbl2 = TO_DOUBLE(str2)
```

| str1:keyword | str2:keyword | dbl:double | dbl1:double | dbl2:double |
| --- | --- | --- | --- | --- |
| 5.20128E11 | foo | 5.20128E11 | 5.20128E11 | null |


Note that in this example, the last conversion of the string isn’t possible.
When this happens, the result is a `null` value. In this case a _Warning_ header is added to the response.
The header will provide information on the source of the failure:

`"Line 1:115: evaluation of [TO_DOUBLE(str2)] failed, treating result as null. Only first 20 failures recorded."`

A following header will contain the failure reason and the offending value:
`"java.lang.NumberFormatException: For input string: "foo""`