Python Sparse data Analysis Package external MRI plugin.

This module contains all the utils tools needed in the p_MRI reconstruction.

mri.operators.gradient.utils.check_lipschitz_cst(f, x_shape, lipschitz_cst, max_nb_of_iter=10)[source]¶

This methods check that for random entrees the lipschitz constraint are statisfied:

• ||f(x)-f(y)|| < lipschitz_cst ||x-y||

Parameters

f: callable

This lipschitzien function

x_shape: tuple

Input data shape

lipschitz_cst: float

The Lischitz constant for the function f

max_nb_of_iter: int

The number of time the constraint must be satisfied

Returns

out: bool

If is True than the lipschitz_cst given in argument seems to be an upper bound of the real lipschitz constant for the function f