Test  Status  Code Input and Output 

1  Fail 
x = spdiags([1 2 3;4 5 6;7 8 9]);
assert(isequal(spdiags(inv_spdiags(x)),x))
m =
0 0 0
0 0 0
0 0 0

2  Fail 
b = spdiags(eye(10));
assert(isequal(spdiags(inv_spdiags(b)),b))
m =
0×10 empty double matrix

3  Fail 
x = spdiags([1 2 3;4 5 6]);
assert(isequal(spdiags(inv_spdiags(x)),x))
m =
0 0
0 0
0 0

4  Fail 
y = spdiags(magic(9));
assert(isequal(spdiags(inv_spdiags(y)),y))
m =
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 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 0

5  Fail 
x = spdiags(magic(5));
assert(isequal(spdiags(inv_spdiags(x)),x))
m =
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

6  Fail 
z = spdiags(ones(10));
assert(isequal(spdiags(inv_spdiags(z)),z))
m =
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
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
0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0

7  Fail 
x = spdiags(randi(10,5));
assert(isequal(spdiags(inv_spdiags(x)),x))
m =
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

8  Fail 
x = spdiags(randi(5,[3 2]));
assert(isequal(spdiags(inv_spdiags(x)),x))
m =
0 0
0 0
0 0

9  Fail 
a = spdiags(zeros(5));
assert(isequal(spdiags(inv_spdiags(a)),a))
m =
0×5 empty double matrix

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