Source code for cr.sparse._src.opt.shrinkage

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import jax.numpy as jnp



[docs]def shrink(a, kappa):
    """Shrinks each entry of a vector by :math:`\\kappa`.

    Entries with magnitude below :math:`\\kappa` go to 0. 
    The magnitude of other entries is reduced by :math:`\\kappa`.
    """
    return jnp.maximum(0, a - kappa) + jnp.minimum(0, a + kappa)