# find missing elements in a matrix

8 views (last 30 days)
Rashmil Dahanayake on 19 Sep 2014
Hi, I have a matrix represents code numbers.
A=[1 2 3 6 7 45 46 47 53 78 80];
B=[55.23 ,74.22]; % B is if same length of A, and contains element by element corresponding data
Say the numbers should be in the range 1:80.
How can I find the numbers which are missing in A.
eg in above case, the expected answer is missing=[4 5 8 9 ... 79]
Then to print a text file
experiment 1 results 55.23
experiment 2 results 442.23
experiment 4 data missing
.
.
experiment 79 data missing
experiment 80 results 442.2
Stephen23 on 19 Sep 2014
Edited: Stephen23 on 19 Sep 2014
• A separate topic.
• Easy to solve yourself using any search engine.
Other users here are not paid to write your code for you, but will happily help if there is something that needs explaining or clarification.
Rashmil Dahanayake on 23 Sep 2014

Stephen23 on 19 Sep 2014
Try setxor :
setxor(A,1:80)
Stephen23 on 19 Sep 2014
Rashmil Dahanayake on 20 Sep 2014
see my updated answer incorporating Fabios

Fabio Freschi on 19 Sep 2014
Try this
A=[1 2 3 6 7 45 46 47 53 78 80];
all = 1:80;
missing = setdiff(all,A);
Fabio
Rashmil Dahanayake on 19 Sep 2014
this method also works

Rashmil Dahanayake on 19 Sep 2014
Edited: Rashmil Dahanayake on 19 Sep 2014
Full Answer for my question asked previously. In case if someone might find it usefull
A=1:3:20; % in complete data
B=1:20; % Full index
missing = setdiff(B,A); % check for missing elements
for ms=1:length(missing)
A=horzcat(A(1:(missing(ms)-1)),'misplaced results',A(missing(ms):end));
end

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