50 lines
1.2 KiB
Python
50 lines
1.2 KiB
Python
s = "Hello"
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for c in s:
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print(c, ord(c))
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print(chr(65))
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# ========== 题目3 ==========
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A = [3, 4]
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B = [1, 2]
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# 1. 向量加法
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def vector_add(a, b):
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return [x + y for x, y in zip(a, b)]
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# 2. 数乘向量
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def scalar_multiply(scalar, vec):
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return [scalar * x for x in vec]
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# 3. 计算向量的模
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def vector_norm(vec):
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return sum(x**2 for x in vec) ** 0.5
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print("题目3：")
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print(f"1. A + B = {vector_add(A, B)}")
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print(f"2. 2 × A = {scalar_multiply(2, A)}")
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print(f"3. A的模 = {vector_norm(A)}")
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print("-" * 30)
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# ========== 题目4 ==========
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A1 = [1, 2, 3]
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B1 = [4, 5, 6]
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A2 = [1, 0]
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B2 = [0, 1]
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# 1. 点积计算
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def dot_product(a, b):
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return sum(x * y for x, y in zip(a, b))
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# 2. 余弦相似度计算
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def cosine_similarity(a, b):
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dot = dot_product(a, b)
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norm_a = vector_norm(a)
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norm_b = vector_norm(b)
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return dot / (norm_a * norm_b) if norm_a != 0 and norm_b != 0 else 0
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print("题目4：")
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print(f"1. A·B = {dot_product(A1, B1)}")
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print(f"2. A1与B1的余弦相似度 = {cosine_similarity(A1, B1):.4f}")
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print(f"3. A2与B2的余弦相似度 = {cosine_similarity(A2, B2)}")
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print(" 原因：两个向量正交（点积为0），方向完全垂直，所以相似度为0") |