MATLAB: How to assign index to array

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Hi,
I have data and want to assign the index to the data as below:
Input data:
col1 col2 col3 col4
1     3   4    9
3     5   5    7
4     6   11   7
0     3   7    2
I want to assign the index as the size of the data, here the size(rows) of the data is 4, then I want to add a column to assign the serial number as below:
Modified data(added 5th column):
1     3   4    9   1
3     5   5    7   2
4     6   11   7   3
0     3   7    2   4

Best Answer

Try
>> M(:,end+1) = reshape( [1:size(M,1)], [],1 );
>> M
M =
     1     3     4     9     1
     3     5     5     7     2
     4     6    11     7     3
     0     3     7     2     4
reshape may be replace by a blip
>> M(:,end+1) = [1:size(M,1)]';
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