import numpy as np
import numpy.linalg as la  # noqa: F401
import pyopencl as cl  # noqa: F401
import pyopencl.array  # noqa
import pyopencl.tools  # noqa
import pyopencl.clrandom  # noqa
import loopy as lp  # noqa


def weno_weights(oscillation, frozen_metric):
    linear = np.array([0.1, 0.6, 0.3])
    eps = 1e-6*frozen_metric

    raw_weights = np.empty((5,3))
    for i in range(5):
        for j in range(3):
            raw_weights[i,j] = linear[j]/(oscillation[i,j] + eps)**2

    weight_sum = raw_weights.sum(axis=1)
    weights = np.empty((5,3))
    for i in range(5):
        for j in range(3):
            weights[i,j] = raw_weights[i,j]/weight_sum[i]

    return weights