MATLAB: How to find the nearest value to a number that is bigger than that number

indexingsort

I'm using the command
[~,indexToClosestMatch] = min(arrayfun(@(x)min(abs(x-val)),matrixcellarray{j}(:,1)));
to find the value in matrixcellarray{j}(:,1) that is closest in value to the number val. I want to additionally specify that I only want to consider values in matrixcellarray{j}(:,1) that are higher than val – i.e. if matrixcellarray{j}(:,1) was [1 2 5 6] and val was 3, I would want it to match to 5, not 2, as although 2 is closer, it is lower than 3. How can I achieve this?

Best Answer

First, your command is overly complicated. arrayfun always pass scalar values to its function, so the x is your anonymous function is always be to be scalar (in turn each element of matrixcellarray{j}(:,1)). So abs(x-val) is scalar, and the minimum of a scalar value is always that value. The arrayfun is completely unnecessary, your code is the same as:
[~, indexToClosestMatch] = min(abs(matrixcellarray{j}(:,1) - val));
There are many ways you could achieve what you want. One way:
distancefromval = matrixcellarray{j}(:,1) - val;  
distancefromval(distancefromval < 0) = +Inf; 
[~, indexToClosestMatch] = min(distancefromval);
Another way:
greaterindices = find(matrixcellarray{j}(:,1) > val); 
[~, intermediateindex] = min(matrixcellarray{j}(greaterindices, 1) - val));
indexToClosestMatch = greaterindices(intermediateindex);
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