Cody

# Problem 2813. Create a block diagonal matrix

Solution 2115277

Submitted on 3 Feb 2020
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### Test Suite

Test Status Code Input and Output
1   Pass
a = [1 2 3]; n = 3; A_correct = [1 2 3 0 0 0 0 0 0; 0 0 0 1 2 3 0 0 0; 0 0 0 0 0 0 1 2 3]; assert(isequal(block_diagonal(a,n),A_correct))

2   Pass
a = []; n = 3; A_correct = []; assert(isequal(block_diagonal(a,n),A_correct))

3   Pass
a = [1 2 -3]'; n = 0; A_correct = []; assert(isequal(block_diagonal(a,n),A_correct))

4   Fail
a = [3 -2]'; n = 4; A_correct = [3 -2 0 0 0 0 0 0; 0 0 3 -2 0 0 0 0; 0 0 0 0 3 -2 0 0; 0 0 0 0 0 0 3 -2]'; assert(isequal(block_diagonal(a,n),A_correct))

Assertion failed.

5   Pass
a = 6; n = 23; A_correct = a*eye(n); assert(isequal(block_diagonal(a,n),A_correct))

6   Fail
a = magic(5); n = 2; A_correct = [a zeros(5); zeros(5) a]; assert(isequal(block_diagonal(a,n),A_correct))

Unable to perform assignment because the size of the left side is 1-by-5 and the size of the right side is 5-by-5. Error in block_diagonal (line 8) A(x,(x-1)*length(a)+1:x*length(a)) = a; Error in Test6 (line 4) assert(isequal(block_diagonal(a,n),A_correct))

7   Fail
a = randi(100,13,8); n = 1; A_correct = a; assert(isequal(block_diagonal(a,n),A_correct))

Unable to perform assignment because the size of the left side is 1-by-13 and the size of the right side is 13-by-8. Error in block_diagonal (line 8) A(x,(x-1)*length(a)+1:x*length(a)) = a; Error in Test7 (line 4) assert(isequal(block_diagonal(a,n),A_correct))