How do I prevent duplicate indexes in an array from subtracting to each other when it satisfies the condition the 1st time?

matA = [21 36 172 246 259 274 303 311 316 322 340 375 377 378 382 396 483 508]

matB = [39 116 198 203 309 314 364 421]

A = 1:1:numel(matA); B=1:1:numel(matB)

for i = A

for j = B

if matA(i) > matB(j)

matA(i)-matB(j)

end

end

end

%order: 172-39=133, 172-116=56, 246-116=130, 246-39=207,246-198=48

%What I want outputted from: 133, 56, 48 (prevent 130 and 207 from happening)

Matlab output:

ans = 133

ans = 56

ans = 207

ans = 130

ans = 48

ans = 43

etc...

Answer 1

[Dyuman Joshi]

matA = [21 36 172 246 259 274 303 311 316 322 340 375 377 378 382 396 483 508];
matB = [39 116 198 203 309 314 364 421];
idx=[];
for i = 1:numel(matA)
    for j = setdiff(1:numel(matB),idx)
            if matA(i) > matB(j) 
                matA(i)-matB(j)
                idx=[idx j];
            end  
    end
end

ans = 133

ans = 56

ans = 48

ans = 43

ans = 2

ans = 2

ans = 11

ans = 62

[Brandon Tsang]

Thanks Dyuman! How would you go about outputting only the highest value out of all the generated for loop outputs?

[Dyuman Joshi]

You can use a value and update it as per the condition -

matA = [21 36 172 246 259 274 303 311 316 322 340 375 377 378 382 396 483 508];
matB = [39 116 198 203 309 314 364 421];
idx=[];
y=-Inf;
for id = 1:numel(matA)
    for jd = setdiff(1:numel(matB),idx)
            if matA(id) > matB(jd) 
                y=max(y,matA(id)-matB(jd));
                idx=[idx jd];
            end  
    end
end
y

y = 133