run_irbp_lib.py

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Created on Tue Oct 26 19:48:48 2021

@author: Xiangyu Yang
"""
import numpy as np
from numpy import linalg as LA

import irbp_lib


def get_sol(point_to_be_projected, p, radius):
    """Test irbp.

    Args:
        point_to_be_projected: Point to be projected.
        p: p parameter for lp-ball.
        radius: The radius of lp-ball.

    Returns:
        x_irbp : The projection point.
    """
    
    data_dim = point_to_be_projected.shape[0]
    
    # Initialization
    x_ini = np.zeros(data_dim, dtype=np.float64)
        
    rand_num = np.random.uniform(0., 1., data_dim)
    rand_num_norm = LA.norm(rand_num, ord=1)
    epsilon_ini = 0.9 * (rand_num * radius / rand_num_norm) ** (1. / p) # ensure that the point is feasible.
        
    x_irbp, dual, runningTime  = irbp_lib.get_lp_ball_projection(x_ini, 
                                             point_to_be_projected, 
                                                                 p, 
                                                            radius, 
                                                       epsilon_ini,
                                                           tau=1.1, 
                                                          tol=1e-8, 
                                                     MAX_ITER=1000)
        
    return x_irbp, dual, runningTime