# random assignment to 1s in a matrix

4 views (last 30 days)
Berfin Çetinkaya on 16 Mar 2022
Commented: Berfin Çetinkaya on 16 Mar 2022
c= birincifaz(:,:)
x=find(c==1)
ja=randi(613,1)
c(x(ja))= randi(10,1)
Hi. I have set up such code. My matrix is very large in 10x69 structure, I want to assign a random number from one to eighteen where 1 is written in the matrix. and it takes too long to assign manually so I want to assign by code. I was able to assign 1 to 1 with this code. How can I set up code about assigning to other 1's? ( Caution ! I wrote birincifaz values below.)
thanks a lot of
birincifaz=
1 1 1 1 1 0 1 1 1 1
0 0 0 0 0 0 1 1 1 1
1 1 1 1 1 0 1 1 1 1
1 1 0 1 1 0 1 1 1 1
1 1 1 1 1 0 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 0 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 0 1 1 1 1
0 0 0 0 0 0 1 0 0 0
1 1 1 1 1 0 1 1 1 1
1 1 1 1 1 0 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 0 1 1 1 1
1 1 1 1 1 0 1 1 1 1
1 1 1 1 1 0 1 1 1 1
1 1 1 1 1 1 1 1 1 1
0 0 0 0 0 0 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 0 1 1 1 1
1 1 1 1 1 0 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1
0 0 0 0 0 0 1 0 0 0
0 0 0 0 0 0 1 0 0 0
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 0 1 1 1 1
1 1 1 1 1 0 1 1 1 1
1 1 1 1 1 1 1 1 1 1
0 0 0 0 0 0 1 0 0 0
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 0 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 0 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 0 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 0 1 1 1 1
1 1 1 1 1 0 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 0 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 0 1 1 1 1
1 1 1 1 1 0 1 1 1 1
1 1 1 1 1 0 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 0 1 1 1 1
1 1 1 1 1 0 1 1 1 1
1 1 1 1 1 0 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 0 1 1 1 1
1 1 1 1 1 1 1 1 1 1

Jan on 16 Mar 2022
Edited: Jan on 16 Mar 2022
I do not understand the question:
"I was able to assign 1 to 1 with this code." - what is the purpose of setting a 1 to a 1?
"How can I set up code about assigning to other 1's?" - which other 1's? Ah, you have changed one single 1 and want to change all. Then:
c = birincifaz; % No need for: (:,:), no need for FIND.
c(c == 1) = randi(18, 1, nnz(c))
Berfin Çetinkaya on 16 Mar 2022
This is the correct answer! Thank you so much.

Davide Masiello on 16 Mar 2022
Edited: Davide Masiello on 16 Mar 2022
c = randi([0,1],69,10) % This replaces your biricinfaz, didn't want to copy that ;)
c = 69×10
0 0 0 0 1 1 1 0 0 0 0 0 0 0 1 1 1 0 1 1 0 0 1 1 1 1 0 1 0 0 1 0 1 1 0 1 1 1 1 1 0 0 1 0 0 0 1 0 1 0 1 0 0 0 1 0 1 0 0 1 0 1 1 1 0 1 1 1 0 1 0 1 0 1 0 0 1 1 0 0 0 1 0 1 1 1 0 1 1 1 0 1 0 0 0 1 1 0 0 0
c(logical(c)) = randi(18,sum(c(:)),1) % This insert random values up to 18 in place of the 1s in c
c = 69×10
0 0 0 0 13 6 14 0 0 0 0 0 0 0 8 11 13 0 7 14 0 0 13 3 10 17 0 11 0 0 8 0 7 2 0 2 1 7 7 16 0 0 8 0 0 0 14 0 12 0 16 0 0 0 10 0 6 0 0 3 0 2 7 8 0 9 5 6 0 6 0 16 0 13 0 0 8 12 0 0 0 14 0 18 11 3 0 11 9 3 0 10 0 0 0 10 6 0 0 0
Berfin Çetinkaya on 16 Mar 2022