How do I make a for loop and use logical operators

For my college class I have this problem Assign numMatches with the number of elements in userValues that equal matchValue. Ex: If matchValue = 2 and userVals = [2, 2, 1, 2], then numMatches = 3.

My code is

function numMatches = FindValues(userValues, matchValue)

      arraySize = 4;     % Number of elements in userValues array
      numMatches = 0;    % Number of elements that equal desired match value
      for i = 1:arraySize 
          if (userValues ~= matchValue) 
              numMatches = arraySize - i
          end
      end
  end

I also tried

If (userValues == matchValue)

but it did not work I tried with a input of FindValues([2, 2, 1, 2], 2) and it didn't work.

any recommendations

Answer 1

[Stephen23]

Counting the non-matches is a creative solution to the problem, and it simply requires counting down from the total number of elements. Your code has a few bugs though, such as:

• you do not increment any counter variable.
• you forgot to use any indexing to select one element from the input array on each loop iteration.
• hard-coding the size of the input array.

These are easily fixed:

function numMatches = FindValues(userValues, matchValue)
numMatches = numel(userValues);
for k = 1:numMatches
    if userValues(k)~=matchValue
        numMatches = numMatches-1
    end
end

There are multiple other ways to solve this problem too. One of the simplest would be simply:

nnz(userValues==matchValue)

e.g.

>> nnz([2,2,1,2] == 2)
ans =  3

[Quentin MckNight]

Thank you so much this really helped me out