How to find elements of an Array using indexes.

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Brandon Bush
Brandon Bush 2018-7-5
编辑： dpb 2018-7-8
I need to find the elements in a 388x2 array by using indexes given by [I]. The indexes can be any number within the 0-388 range and there are 31 total.
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Brandon Bush
Brandon Bush 2018-7-5
The SAT_RNFL and RNFLS arrays are just rainfall totals and have nothing to do with the coordinates
Brandon Bush
Brandon Bush 2018-7-5
Also when the loop finishes, the only thing that gets mapped to I is the last value, however, when I use disp(I) it prints out all the indices

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dpb
dpb 2018-7-5
编辑：dpb 2018-7-8
for i = 1:31
[Y, I] = min((latS-latG(i)).^2 + (lonS-lonG(i)).^2);
disp(I)
...
" %Prints indices of the matched coordinates"
But this is only sequentially through the loop for each element in turn, you haven't saved the found location; each pass overwrites the previous so indeed when the loop finishes all you have is the last iteration.
The most "deadahead" solution given the existing code would be
N=31;
Y=zeros(N,1); I=Y; % preallocate
for i = 1:N
[Y(i), I(i)] = min((latS-latG(i)).^2 + (lonS-lonG(i)).^2);
...
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Brandon Bush
Brandon Bush 2018-7-5
It didnt quite work. It gave me indices that didnt coordinate with those represented by I
dpb
dpb 2018-7-8
I guess I misinterpreted what you were asking for...I thought the I was a "pick 'em" vector to select a subset, not a predefined set of indices. Your problem is outlined in revised Answer...

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