Tallying in nested arrays and returning the object-CodePudding

Looking for some help with a problem as I'm very new to Javascript.

I want to write a function that tallies up feedback scores as shown in the code below. I want to take an array with nested arrays and if the score given is below 3 it should increase the negative property, if it's in the range 4 - 6 the neutral property should increase and when it's in the 7 - 10 range, it's positive that should increase.

I continue to simply receive in the console log

{positive: 0, negative: 0, neutral: 0}

which obviously isn't the expected output. What is wrong?

function gatherFeedback(feedbackArray) {
  let result = {
    positive: 0,
    negative: 0,
    neutral: 0
  };

  if (feedbackArray > 0) {
    for (let i = 0; i < feedbackArray; i  ) {
      if (feedbackArray[i][1] >= 7) {
        result.positive  
      } else if (feedbackArray[i][1] <= 3) {
        result.negative  
      } else if (feedbackArray[i][1] > 3 && feedbackArray < 7) {
        result.neutral  
      }
    }
  }
  return result;
}

console.log(gatherFeedback([
  ['feedback1', 10],
  ['feedback2', 3],
  ['feedback3', 6]
]))

CodePudding user response：

Your main issue is with this line:

if(feedbackArray > 0){

When you try to compare an array to an integer the array first gets converted into a string, which in this case yields:

"feedback1,10,feedback2,3,feedback3,6"

comparing this to 0 yields false (see the description here as to why) so your loop never runs. The same problem will apply with the next line where you have:

i < feedbackArray

It's simpler just to use a for...of loop (note you can also simplify your if/else structure):

function gatherFeedback(feedbackArray) {
  let result = {
    positive: 0,
    negative: 0,
    neutral: 0
  };

  for (let f of feedbackArray) {
    if (f[1] >= 7) {
      result.positive  
    } else if (f[1] > 3) {
      result.neutral  
    } else {
      result.negative  
    }
  }
  return result;
}

console.log(gatherFeedback([
  ['feedback1', 10],
  ['feedback2', 3],
  ['feedback3', 6]
]))

CodePudding user response：

Change your code to this

function gatherFeedback (feedbackArray) {
    let result = {positive: 0, negative: 0, neutral: 0};
    if(feedbackArray.length > 0){
        for(let i = 0; i < feedbackArray.length; i  ) {
            if(feedbackArray[i][1] >= 7) {
                result.positive  
            } else if(feedbackArray[i][1] <= 3){
                result.negative  
            } else if (feedbackArray[i][1] > 3 && feedbackArray[i][1] < 7) {
                result.neutral  
            }
        }   
    }
    return result;
}

CodePudding user response：

Use .length array property:

function gatherFeedback(feedbackArray) {

  let result = {
    positive: 0,
    negative: 0,
    neutral: 0
  };

  if (feedbackArray.length > 0) {
    for (let i = 0; i < feedbackArray.length; i  ) {
      if (feedbackArray[i][1] >= 7) {
        result.positive  
      } else if (feedbackArray[i][1] <= 3) {
        result.negative  
      } else if (feedbackArray[i][1] > 3 && feedbackArray < 7) {
        result.neutral  
      }
    }
  }
  return result;
}

console.log(gatherFeedback([
  ['feedback1', 10],
  ['feedback2', 3],
  ['feedback3', 6]
]))