IndicatorBox

class odl.functionals.default_functionals.IndicatorBox(*args, **kwargs)[source]

Indicator on some box shaped domain.

Notes

The indicator $F$ with lower bound $a$ and upper bound $b$ is defined as:

$F(x) = \begin{cases} 0 & \text{if } a \leq x \leq b \text{ everywhere}, \\ \infty & \text{else} \end{cases}$

__init__(space, lower=None, upper=None)[source]

Initialize an instance.

spaceLinearSpace: Domain of the functional.
lowerspace.field element or space element-like, optional: The lower bound. Default: None, interpreted as -infinity
upperspace.field element or space element-like, optional: The upper bound. Default: None, interpreted as +infinity

>>> space = odl.rn(3)
>>> func = IndicatorBox(space, 0, 2)
>>> func([0, 1, 2])  # all points inside
0
>>> func([0, 1, 3])  # one point outside
inf