## helper()


Apply a square-root transformation to a single value.


Usage


``` python
helper(x)
```


Computes the square root of the absolute value of `x`, preserving the original sign.


## Parameters


`x: float`  
A numeric value to transform.


## Returns


`float`  
The signed square root: `sign(x) * sqrt(abs(x))`.


## Notes

This function is used internally by [advanced_compute()](advanced_compute.md#gdtest_docstring_combo.advanced_compute) for element-wise data transformation.


## Examples

``` python
>>> helper(4.0)
```

2.0

``` python
>>> helper(-9.0)
```

-3.0

``` python
>>> helper(0.0)
```

0.0