# SigmoidTransform

Source: https://www.tensorplay.cn/docs/generated/tensorplay.distributions.SigmoidTransform.html

```python
class tensorplay.distributions.SigmoidTransform(cache_size: int = 0)
```

Transform via the mapping $y = \frac{1}{1 + \exp(-x)}$ and $x = \text{logit}(y)$.

```python
forward_shape(shape)
```

Infers the shape of the forward computation, given the input shape.
Defaults to preserving shape.

```python
property inv: Transform
```

Returns the inverse [Transform](/docs/generated/tensorplay.distributions.Transform.html#tensorplay.distributions.Transform) of this transform.
This should satisfy t.inv.inv is t.

```python
inverse_shape(shape)
```

Infers the shapes of the inverse computation, given the output shape.
Defaults to preserving shape.