Source code for qgs.functions.util

    Utility functions module

    This module has some useful functions for the model.


import numpy as np
from numba import njit

[docs]@njit def reverse(a): """Numba-jitted function to reverse a 1D array. Parameters ---------- a: ~numpy.ndarray The 1D array to reverse. Returns ------- ~numpy.ndarray The reversed array. """ out = np.zeros_like(a) ii = 0 for i in range(len(a)-1,-1,-1): out[ii] = a[i] ii +=1 return out
[docs]@njit def normalize_matrix_columns(a): """Numba-jitted function to normalize the columns of a 2D array to one. Parameters ---------- a: ~numpy.ndarray The 2D array to column-normalize. Returns ------- ~numpy.ndarray The normalized array. """ an = np.zeros_like(a) norm = np.zeros(a.shape[0]) for i in range(a.shape[1]): norm[i] = np.linalg.norm(a[:, i], 2) an[:, i] = a[:, i] / norm[i] return an, norm
[docs]@njit def solve_triangular_matrix(a, b): """Solve a triangular linear matrix equation :math:`ax = b`. Parameters ---------- a: ~numpy.ndarray The 2D array :math:`a`. b: ~numpy.ndarray The 2D array :math:`b`. Returns ------- ~numpy.ndarray The 2D array of solution :math:`x`. """ x = np.zeros_like(a) for i in range(2, a.shape[0]+1): x[:i, i - 1] = np.linalg.solve(a[:i, :i], b[:i, i - 1]) x[0, 0] = b[0, 0] / a[0, 0] return x