Problem 7. Column Removal

Solution 535203

Submitted on 25 Nov 2014

Size: 31
Leading solution size is 7.

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2 Comments

2 Comments

VIVEK RUHELA on 25 Nov 2014

can anybody tell me why this solution is not working:"[a,b] = qr(A);
[a1,b1] = qrdelete(a,b,n);
y = a1*b1;"
Although it gives right answers to all test Suits in the software.Plz

Zikobrelli on 27 Nov 2014

because of rounding errors.
B = round(a1*b1);
it should work in this case as all numbers are integers.

Test Suite

Test	Status	Code Input and Output
1	Fail	%% A = [1 2 3; 4 5 6]; n = 2; B_correct = [1 3; 4 6]; assert(isequal(column_removal(A,n),B_correct)) Error: Assertion failed.
2	Fail	%% A = magic(4); n = 3; B = [16 2 13; 5 11 8; 9 7 12; 4 14 1]; B_correct = B; assert(isequal(column_removal(A,n),B_correct)) Error: Assertion failed.
3	Pass	%% A = 1:10; n = 7; B_correct = [1 2 3 4 5 6 8 9 10]; assert(isequal(column_removal(A,n),B_correct))

Test

Status

Code Input and Output

Fail

%% A = [1 2 3; 4 5 6]; n = 2; B_correct = [1 3; 4 6]; assert(isequal(column_removal(A,n),B_correct))

Error: Assertion failed.

Fail

%% A = magic(4); n = 3; B = [16 2 13; 5 11 8; 9 7 12; 4 14 1]; B_correct = B; assert(isequal(column_removal(A,n),B_correct))

Error: Assertion failed.

Pass

%% A = 1:10; n = 7; B_correct = [1 2 3 4 5 6 8 9 10]; assert(isequal(column_removal(A,n),B_correct))

Problem 7. Column Removal

Test Suite

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Problem 7. Column Removal

Test Suite

Suggested Problems

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