Masked Fill

Replace elements in a tensor where a boolean mask is True with a given fill value.

Input:

• x: A tensor of any shape
• mask: A boolean tensor of the same shape (1.0 = True, 0.0 = False)
• fill_value: The value to fill where mask is True

Output: A tensor of the same shape with masked positions replaced by fill_value.

API Reference:

• PyTorch: x.masked_fill(mask, fill_value) or torch.where(mask, fill_value, x)
• JAX: jnp.where(mask, fill_value, x)