Loop is not reading from the first value in the array?
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I have a loop that is transferring data between two arrays, however, I'm not sure why it is not reading from the very first and last values. The first array (arrayA) looks like:
{'7'} {'ans'} {[1]}
{'7'} {'ans'} {[2]}
{'7'} {'ans'} {[3]}
second array (arrayB) looks like:
{'7' } {[101]} {[1]}
{'ans'} {[278]} {[1]}
{'7' } {[299]} {[2]}
{'ans'} {[300]} {[2]}
{'7' } {[432]} {[3]}
{'ans'} {[467]} {[3]}
With the following loop, IF the value in arrayA{a,3} matches that in arrayB{b,3}, i want the FIRST matching value to appear in arrayB{b,4} and the SECOND matching value to appear in arrayB{b,5}.
for a = 1:length(arrayA)
for b = 1:length(arrayB)
if arrayA{a,3}==arrayB{b,3}
arrayA{a,4} = arrayB{b,2};
arrayA{a,5} = arrayB{(b+1),2};
end
end
end
Right now, it looks like:
{'7'} {'ans'} {[1]} {[278]} {[299]}
{'7'} {'ans'} {[2]} {[300]} {[432]}
{'7'} {'ans'} {[3]} {[467]} {[467]}
What I would like however would be:
{'7'} {'ans'} {[1]} {[101]} {[278]}
{'7'} {'ans'} {[2]} {[299]} {[300]}
{'7'} {'ans'} {[3]} {[432]} {[467]}
2 个评论
Rik
2018-8-8
What is the goal of this code? What are you trying to achieve? Also, (b-1)+1 is just b, so is that a typo?
I think I would use ismember(arrayA,arrayB) to get a list of valid positions, but that is just a gut feeling without knowing a bit more about your goal and what sort of data to expect.
Jasmine Karim
2018-8-9
采纳的回答
Fangjun Jiang
2018-8-9
0 个投票
It is because third column in B has duplicated values. For example, the result of the first loop (b=1) in the "for b = 1:length(arrayB)" loop is over-written by the second loop (b=2)
5 个评论
Jasmine Karim
2018-8-9
Fangjun Jiang
2018-8-9
You have to tell first, how to deal (non programming) with this case (duplicated value in third column of B)
Jasmine Karim
2018-8-9
Fangjun Jiang
2018-8-9
for a = 1:size(arrayA,1)
Col=3;
for b = 1:size(arrayB,1)
if arrayA{a,3}==arrayB{b,3}
Col=Col+1;
arrayA{a,Col} = arrayB{b,2};
end
end
end
Note that size() is better than length() for your case.
Jasmine Karim
2018-8-9
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