85 lines
2.3 KiB
Python
85 lines
2.3 KiB
Python
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import random
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class Matrix:
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def __init__(self, rows, cols):
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self.rows = rows
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self.cols = cols
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self.data = []
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for i in range(0, rows):
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self.data.append([0 for _ in range(0, cols)])
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@staticmethod
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def from_list(lst):
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m = Matrix(len(lst), 1)
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m.map(lambda x, i, j: lst[i])
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return m
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@staticmethod
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def product(a, b):
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"""Matrix product"""
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if a.cols != b.rows:
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return None
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result = Matrix(a.rows, b.cols)
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result.map(lambda x, i, j: sum([a.data[i][k] * b.data[k][j] for k in range(0, a.cols)]))
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return result
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@staticmethod
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def transpose(m):
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"""Transpose a matrix"""
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result = Matrix(m.cols, m.rows)
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result.map(lambda x, i, j: m.data[j][i])
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return result
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@staticmethod
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def subtract(a, b):
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result = Matrix(a.rows, a.cols)
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result.map(lambda x, i, j: a.data[i][j] - b.data[i][j])
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return result
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@staticmethod
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def clone(m):
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result = Matrix(m.rows, m.cols)
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result.map(lambda x, i, j: m.data[i][j])
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return result
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def map(self, fun):
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"""Execute a function on every element of the list, use the return value as the new value of the element"""
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for i in range(0, self.rows):
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for j in range(0, self.cols):
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self.data[i][j] = fun(self.data[i][j], i, j)
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def randomize(self):
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"""Fill the matrix with random integers"""
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self.map(lambda x, i, j: random.randint(-1, 1))
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def multiply(self, n):
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"""Hadamard or scalar product"""
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if type(n) is Matrix:
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self.map(lambda x, i, j: x * n.data[i][j])
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else:
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self.map(lambda x, i, j: x * n)
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def add(self, n):
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"""Entrywise or scalar addition"""
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if type(n) is Matrix:
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self.map(lambda x, i, j: x + n.data[i][j])
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else:
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self.map(lambda x, i, j: x + n)
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def print(self):
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"""Pretty print the matrix"""
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for row in self.data:
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for elem in row:
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print(elem, end='\t')
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print()
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def to_list(self):
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"""Returns the internal matrix as a list"""
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lst = []
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self.map(lambda x, i, j: lst.append(x))
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return lst
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