bem.py 文件源码

def _compute_linear_parameters(mu, u):
    """Compute the best-fitting linear parameters"""
    _compose_linear_fitting_data(mu, u)
    uu, sing, vv = linalg.svd(u['M'], full_matrices=False)

    # Compute the residuals
    u['resi'] = u['y'].copy()

    vec = np.empty(u['nfit'] - 1)
    for p in range(u['nfit'] - 1):
        vec[p] = np.dot(uu[:, p], u['y'])
        for k in range(u['nterms'] - 1):
            u['resi'][k] -= uu[k, p] * vec[p]
        vec[p] = vec[p] / sing[p]

    lambda_ = np.zeros(u['nfit'])
    for p in range(u['nfit'] - 1):
        sum_ = 0.
        for q in range(u['nfit'] - 1):
            sum_ += vv[q, p] * vec[q]
        lambda_[p + 1] = sum_
    lambda_[0] = u['fn'][0] - np.sum(lambda_[1:])
    rv = np.dot(u['resi'], u['resi']) / np.dot(u['y'], u['y'])
    return rv, lambda_