what is the single command?????????

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VIJAY on 17 Aug 2018
Commented: VIJAY on 20 Aug 2018
I want to create matrix size is 100*12. Each row contain only 5 zeros other elements are 1. for ex
A=[1 1 1 0 0 1 1 0 0 0 1 1 ;
0 0 1 1 0 0 1 1 0 1 1 1;]
Note: Nobody row is repeated
VIJAY on 17 Aug 2018
thank you guy but rows are repeated.........

Stephen on 17 Aug 2018
Edited: Stephen on 17 Aug 2018
R = 100; % rows
C = 12; % columns
N = 5; % number of 1's.
cmb = nchoosek(1:C,N); % all unique column combinations.
idx = randperm(size(cmb,1)); % indices to randomize combinations.
idc = cmb(idx(1:R),:); % (col index) pick first 100 random combinations.
idr = ndgrid(1:R,1:N); % (row index).
mat = ones(R,C); % preallocate output matrix.
mat(sub2ind([R,C],idr,idc)) = 0
Check:
>> all(sum(mat,2)==7) % all rows sum to seven.
ans = 1
>> all(ismember(mat(:),0:1)) % only 0's and 1's.
ans = 1
>> size(unique(mat,'rows')) % all rows are unique.
ans =
100 12
Stephen on 17 Aug 2018
@VIJAY: I hope that it helps. Remember to accept the answer. Accepting my answer is the easiest way to thank me.

Rik on 17 Aug 2018
First generate all combinations, and then select 100 from them:
total_row_length=12;
number_of_zeros=5;
selected_number_of_rows=100;
v=1:total_row_length;
col_positions = nchoosek(v,number_of_zeros);
row_positions=repmat((1:size(col_positions,1))',1,size(col_positions,2));
out=ones(size(col_positions,1),total_row_length);
inds=sub2ind(size(out),row_positions,col_positions);
out(inds)=0;
%select a random sample from all possible rows
selected_rows=randperm(size(out,1),selected_number_of_rows);
result=out(selected_rows,:);
VIJAY on 20 Aug 2018