Problem 1051. Exact binary matrix factorization

Solution 167480

Submitted on 24 Nov 2012

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Paul Peeling on 24 Nov 2012

very interesting observation that lu returns binary values factors for
these inputs. i must think about this further!

Test	Status	Code Input and Output
1	Fail	%% C = [1 1 1 0 0 0 0 0 0 1 0 1]; K = 2; [A,B] = ebmf(C,K); assert(isequal(A*B,C)) assert(isequal(unique(A),[0; 1])) assert(isequal(unique(B),[0; 1])) assert(all(size(A)==[size(C,1),K])) assert(all(size(B)==[K,size(C,2)])) Error: Assertion failed.
2	Pass	%% C = [1 0 0 1 0 0 1 1 0]; K = 3; [A,B] = ebmf(C,K); assert(isequal(A*B,C)) assert(isequal(unique(A),[0; 1])) assert(isequal(unique(B),[0; 1])) assert(all(size(A)==[size(C,1),K])) assert(all(size(B)==[K,size(C,2)]))
3	Fail	%% C = [0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 1 1 1 0 1 0 1 0 0 0 1 1 1 0 1 0 1 0 0 0 1 1 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0]; K = 1; [A,B] = ebmf(C,K); assert(isequal(A*B,C)) assert(isequal(unique(A),[0; 1])) assert(isequal(unique(B'),[0; 1])) assert(all(size(A)==[size(C,1),K])) assert(all(size(B)==[K,size(C,2)])) Error: Assertion failed.
4	Fail	%% Added another small test case C = [1 0 1 1 1 1 0 1 0]; K = 2; [A,B] = ebmf(C,K); assert(isequal(A*B,C)) assert(isequal(unique(A),[0; 1])) assert(isequal(unique(B'),[0; 1])) assert(all(size(A)==[size(C,1),K])) assert(all(size(B)==[K,size(C,2)])) Error: Assertion failed.
5	Fail	%% A degenerate problem C = [0 0 1 0 0 0 0 0 1]; K = 2; [A,B] = ebmf(C,K); assert(isequal(A*B,C)) assert(isequal(unique(A),[0; 1])) assert(isequal(unique(B'),[0; 1])) assert(all(size(A)==[size(C,1),K])) assert(all(size(B)==[K,size(C,2)])) Error: Assertion failed.