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Dot Product
Problem Statement
Compute dot products and matrix multiplications.
Background
NumPy provides several multiplication operations:
- np.dot(a, b) - dot product
- a @ b - matrix multiplication (Python 3.5+)
- a * b - element-wise multiplication
For vectors: dot product = sum of element-wise products For matrices: standard matrix multiplication
Your Task
Write a function compute_products(vec1, vec2, mat) that computes various products.
Output Format
Return a dictionary with:
- "dot": Dot product of vec1 and vec2 (scalar)
- "elementwise": Element-wise product of vec1 and vec2 (list)
- "mat_vec": Matrix times vec1 (list)
- "vec_mat": vec1 times matrix (list)
Example:
Input:
vec1 = [1,2,3], vec2 = [4,5,6], mat = identity
Output:
{'dot': 32, 'elementwise': [4, 10, 18], 'mat_vec': [1, 2, 3], 'vec_mat': [1, 2, 3]}Reasoning:
Dot: 14+25+36=32, elementwise: [14, 25, 36], identity matrix preserves vectors
Constraints:
- vec1 and vec2 have same length
- mat is square with size matching vector length
Editor
Python 3.13.1
Test Results
0/0Run code to see test results.