import unittest
import numpy as np
import user_code  # ÐºÐ¾Ð´ ÑÑÑÐ´ÐµÐ½ÑÐ°

def _dynamic(tc, ok, ok_msg, fail_msg):
    tc._testMethodName = ok_msg if ok else fail_msg
    (tc.assertTrue if ok else tc.fail)(tc._testMethodName)

ATOL = 1e-8
RTOL = 1e-7

class TestLUChallenge(unittest.TestCase):

    def test_variables_exist_and_shapes(self):
        reasons = []
        A = getattr(user_code, "A", None)
        b = getattr(user_code, "b", None)
        L = getattr(user_code, "L", None)
        U = getattr(user_code, "U", None)
        y = getattr(user_code, "y", None)
        x = getattr(user_code, "x", None)

        if not (isinstance(A, np.ndarray) and A.shape == (3,3)):
            reasons.append(f"A must be 3x3 ndarray; got {None if A is None else A.shape}")
        if not (isinstance(b, np.ndarray) and b.shape == (3,)):
            reasons.append(f"b must be shape (3,); got {None if b is None else b.shape}")
        if not (isinstance(L, np.ndarray) and L.shape == (3,3)):
            reasons.append(f"L must be 3x3 ndarray; got {None if L is None else L.shape}")
        if not (isinstance(U, np.ndarray) and U.shape == (3,3)):
            reasons.append(f"U must be 3x3 ndarray; got {None if U is None else U.shape}")
        if not (isinstance(y, np.ndarray) and y.shape == (3,)):
            reasons.append(f"y must be shape (3,); got {None if y is None else y.shape}")
        if not (isinstance(x, np.ndarray) and x.shape == (3,)):
            reasons.append(f"x must be shape (3,); got {None if x is None else x.shape}")

        _dynamic(self,
                 len(reasons) == 0,
                 "PASS: variables exist with correct shapes",
                 "FAIL: " + " | ".join(reasons) if reasons else "FAIL")

    def test_LU_structure_and_reconstruction(self):
        reasons = []
        A, L, U = user_code.A, user_code.L, user_code.U

        # L: ones on diagonal, zeros above
        if not np.allclose(np.diag(L), np.ones(3), atol=ATOL, rtol=RTOL):
            reasons.append("L diagonal must be all ones")
        if not np.allclose(np.triu(L, k=1), np.zeros_like(np.triu(L, k=1)), atol=ATOL, rtol=RTOL):
            reasons.append("L must be lower triangular (zeros above diagonal)")

        # U: zeros below diagonal
        if not np.allclose(np.tril(U, k=-1), np.zeros_like(np.tril(U, k=-1)), atol=ATOL, rtol=RTOL):
            reasons.append("U must be upper triangular (zeros below diagonal)")

        # Reconstruction
        if not np.allclose(L @ U, A, atol=1e-7, rtol=1e-6):
            reasons.append("L @ U does not reconstruct A within tolerance")

        _dynamic(self,
                 len(reasons) == 0,
                 "PASS: L/U structure and A â L@U",
                 "FAIL: " + " | ".join(reasons) if reasons else "FAIL")

    def test_forward_and_backward(self):
        reasons = []
        A, b, L, U, y, x = user_code.A, user_code.b, user_code.L, user_code.U, user_code.y, user_code.x

        # Forward: Ly â b
        if not np.allclose(L @ y, b, atol=1e-7, rtol=1e-6):
            reasons.append("Forward substitution incorrect: L @ y != b")

        # Backward: Ux â y
        if not np.allclose(U @ x, y, atol=1e-7, rtol=1e-6):
            reasons.append("Backward substitution incorrect: U @ x != y")

        _dynamic(self,
                 len(reasons) == 0,
                 "PASS: forward (Ly=b) & backward (Ux=y) checks",
                 "FAIL: " + " | ".join(reasons) if reasons else "FAIL")

    def test_solution_matches_numpy(self):
        reasons = []
        A, b, x = user_code.A, user_code.b, user_code.x
        x_np = np.linalg.solve(A, b)

        if not np.allclose(x, x_np, atol=1e-7, rtol=1e-6):
            reasons.append(f"x does not match np.linalg.solve: expected {x_np}, got {x}")

        _dynamic(self,
                 len(reasons) == 0,
                 "PASS: x matches NumPy solution",
                 "FAIL: " + " | ".join(reasons) if reasons else "FAIL")


test_code.py

Beheers de wiskundige basisprincipes die essentieel zijn voor data science. Verken kernconcepten in functies, calculus, lineaire algebra, kansrekening en dimensiereductie. Bouw zowel theoretisch inzicht als praktische programmeerervaring op om uw vermogen te versterken om data te analyseren, complexe systemen te modelleren en geavanceerde technieken in machine learning toe te passen.

Verken de basis van wiskundige functies. Maak kennis met verschillende typen algebraïsche en transcendente functies, hun eigenschappen en de implementatie ervan in Python voor het oplossen van praktijkproblemen.

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Ontwikkel een grondig begrip van limieten, afgeleiden, integralen en partiële afgeleiden. Verbind theorie met praktijk door deze concepten te implementeren in Python en toe te passen op optimalisatie via gradient descent.

Solide kennis van vectoren, matrices en transformaties. Inzicht in ontbindingsmethoden en eigenwaardeanalyse, met versterking van concepten door Python-programmeeruitdagingen en praktische toepassingen in data science.

Verdiep u in kansrekening en statistiek. Bestudeer conditionele kans, de stelling van Bayes en statistische maten. Implementeer kernconcepten in Python, simuleer verdelingen en versterk uw vaardigheden met uitdagingen en quizzen.

Uitdaging: Oplossen van een Lineair Stelsel met LU-Decompositie

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