Create 121x121 Matrix in MATLAB with 0s, 1s and -4s

[monsmatglad]

I need to create a 121*121 matrix in matlab. Forty of the rows have to contain the sequence 0 1 0 0 1 -4 1 0 0 1. and the rest of the rows will have 0's and "one 1" per row. The sequence has to be pushed one step to the right from row 1 to 121, the result should be a matrix with only -4's and 1's on the diaogonal.

The first 12 rows will have the form:
1 0 0 0 0 0 0 0 0 0 0...
0 1 0 0 0 0 0 0 0 0 0...
0 0 1 0 0 0 0 0 0 0 0...

Then the rows with the -4's appear 9 times being separated by only two rows of type 1 and 0.
example:
1 0 0 0 0 0 0 0 0 0 0...
0 1 0 0 0 0 0 0 0 0 0...
0 0 1 0 0 0 0 0 0 0 0...
11 rows
then
9 rows of
0 1 0 0 1 -4 1 0 0 1 0 0 0 0 0 0 0 0 0...
0 0 1 0 0 1 -4 1 0 0 1 0 0 0 0 0 0 0 ...
0 0 0 1 0 0 1 -4 1 0 0 1 0 0 0 ...
after the 9 rows then two of only 1 and 0 again. and it continues like that for 110 rows down, with the remaining being like the twelve first with only 1 and zeros.

phew! Hope this is possible to understand. I have very little experience with programing, so I find this really hard.
2. Homework Equations
please ask for expanation if you don't understand.

3. The Attempt at a Solution

Mons
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[lippyka]

Matrix = zeros(121); % creates a 121x121 matrix of zerosfor i=1:12 % loop to fill the first 12 rows with the sequence 1 0 0 0 0 0 0 0 0 0 0... Matrix(i,i)=1;endfor i=13:110 % loop to fill the next 98 rows with the sequence 0 1 0 0 1 -4 1 0 0 1 0 0 0 0 0 0 0 0 ... Matrix(i,i-1) = 1; Matrix(i,i) = 0; Matrix(i,i+1) = 1; Matrix(i,i+4) = -4; Matrix(i,i+5) = 1; Matrix(i,i+8) = 1;endfor i=111:121 % loop to fill the last 11 rows with the sequence 0 0 1 0 0 0 0 0 0 0 0 ... Matrix(i,i)=1;end