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beafe3656f
* Change some Image File names & re-code the psnr algorithm (conserving both methods). Also Added new example. * Selected psnr method and reformat some code from arithmetic_analysis
33 lines
944 B
Python
33 lines
944 B
Python
# lower–upper (LU) decomposition - https://en.wikipedia.org/wiki/LU_decomposition
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import numpy
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def LUDecompose (table):
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# Table that contains our data
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# Table has to be a square array so we need to check first
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rows,columns=numpy.shape(table)
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L=numpy.zeros((rows,columns))
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U=numpy.zeros((rows,columns))
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if rows!=columns:
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return []
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for i in range (columns):
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for j in range(i-1):
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sum=0
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for k in range (j-1):
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sum+=L[i][k]*U[k][j]
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L[i][j]=(table[i][j]-sum)/U[j][j]
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L[i][i]=1
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for j in range(i-1,columns):
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sum1=0
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for k in range(i-1):
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sum1+=L[i][k]*U[k][j]
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U[i][j]=table[i][j]-sum1
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return L,U
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if __name__ == "__main__":
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matrix =numpy.array([[2,-2,1],
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[0,1,2],
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[5,3,1]])
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L,U = LUDecompose(matrix)
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print(L)
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print(U)
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