CHAMP's fallback of "taking a small step" during halfspace intersection seems to retur

The fix in <a class="commit-link" data-hovercard-type="commit" data-hovercard-url="htt

Refuse to use CHAMP's small step interior point calculation about modularitypruning HOT 2 CLOSED

ragibson commented on June 13, 2024

Refuse to use CHAMP's small step interior point calculation

from modularitypruning.

Comments (2)

ragibson commented on June 13, 2024

Since the halfspace intersection algorithm uses a duality that changes distances from the interior point to their inverses, it seems CHAMP's small step fallback

    # take a small step into interior from 1st plane.
    dim = hs_list.shape[1] - 1  # hs_list has shape (number of halfspaces, dimension+1)
    intpt = np.array([0 for _ in range(dim - 1)] + [np.max(z_vals)])
    internal_step = np.array([.000001 for _ in range(dim)])
    return intpt + internal_step

is actually more stable if you take a larger step (since inverting the distances isn't as extreme then). For example,

    # take a small step into interior from 1st plane.
    dim = hs_list.shape[1] - 1  # hs_list has shape (number of halfspaces, dimension+1)
    intpt = np.array([0 for _ in range(dim - 1)] + [np.max(z_vals)])
    internal_step = np.array([1 for _ in range(dim)])
    return intpt + internal_step

from modularitypruning.

ragibson commented on June 13, 2024

The fix in wweir827/CHAMP@8cbfd64 should resolve this issue (at least partially).

from modularitypruning.

Recommend Projects