[source] # Sigmoidal S shaped nonliearity kernel with output values ranging from -1 to 1. ## Parameters | # | Name | Default | Type | Description | |---|---|---|---|---| | 1 | gamma | null | float | The kernel coefficient. | | 2 | coef0 | 0. | float | The independent term. | ## Example ```php use Rubix\ML\Kernels\SVM\Sigmoidal; $kernel = new Sigmoidal(null, 0.); ```