How to add lower triangle of zeros/indent to each row, in a matrix?

I have this matrix:

1 2 3 4 5 6 7 8 5 5
3 3 3 3 3 4 4 4 5 5
1 4 3 4 3 4 4 4 5 5
3 3 3 3 4 4 4 5 5 5 

And I want this as the result:

1 2 3 4 5 6 7 8 5 5 0 0 0
0 3 3 3 3 3 4 4 4 5 5 0 0
0 0 1 4 3 4 3 4 4 4 5 5 0
0 0 0 3 3 3 3 4 4 4 5 5 5 

How can I do this as a script?

Please help

Thank you

[Catalytic]

It appears that you have not Accept-clicked any of the answers you have been given to your other questions.

Were they all unhelpful?

Answer 1

[Matt J]

B=[1 2 3 4 5 6 7 8 5 5
3 3 3 3 3 4 4 4 5 5
1 4 3 4 3 4 4 4 5 5
3 3 3 3 4 4 4 5 5 5];

[m,n]=size(B);

result=spdiags(B,0:n-1,m,n+m-1);

full(result)

ans = 4×13

1 2 3 4 5 6 7 8 5 5 0 0 0 0 3 3 3 3 3 4 4 4 5 5 0 0 0 0 1 4 3 4 3 4 4 4 5 5 0 0 0 0 3 3 3 3 4 4 4 5 5 5

[Amanda]

I can't even begin to express my appreciation for you. You deserve that upvote.

[Matt J]

You're quite welcome, but please Accept-click the answer to indicate that it resolved the problem.

[Amanda]

Done