Codecademy export

main.js

// Returns a random DNA base
const returnRandBase = () => {
  const dnaBases = ['A', 'T', 'C', 'G']
  return dnaBases[Math.floor(Math.random() * 4)] 
}

// Returns a random single strand of DNA containing 15 bases
const mockUpStrand = () => {
  const newStrand = []
  for (let i = 0; i < 15; i++) {
    newStrand.push(returnRandBase())
  }
  return newStrand
}

function pAequorFactory(specimenNum, dna) {
  return {
    specimenNum,
    dna,
    mutate() {
      console.log(dna)
      let randomIndex = Math.floor(Math.random() * dna.length);
      let randomBase = dna[randomIndex];
      // console.log(randomBase);
      switch (randomBase) {
        case 'A':
          let replaceA = ['T', 'C', 'G'];
          randomBase = replaceA[Math.floor(Math.random() * replaceA.length)];
          break;
        case 'T':
          let replaceT = ['A', 'C', 'G'];
          randomBase = replaceT[Math.floor(Math.random() * replaceT.length)]
          break;
        case 'C':
          let replaceC = ['T', 'A', 'G'];
          randomBase = replaceC[Math.floor(Math.random() * replaceC.length)]
          break;
        case 'G':
          let replaceG = ['T', 'C', 'A'];
          randomBase = replaceG[Math.floor(Math.random() * replaceG.length)]
          break;
        default:
          console.log('False alarm!')
      }
      dna[randomIndex] = randomBase;
      console.log(dna)
      return dna
    },
    compareDNA(pAequorObj) {
      let counter = 0;
      let percent;
      for (let i = 0; i < pAequorObj.dna.length; i++) {
        if (dna[i] === pAequorObj.dna[i]) {
          counter += 1
        }
      }
      percent = ((counter / dna.length) * 100).toFixed(2);
      console.log(`specimen #1 and specimen #2 have ${percent}% DNA in common`)
    },
    willLikelySurvive() {
      let counterC = 0;
      let counterG = 0
      dna.forEach(letter => {
        if (letter === 'C') {
          counterC++;
        } else if (letter === 'G') {
          counterG++;
        }
      });

      let percentC = ((counterC / dna.length) * 100).toFixed(2);
      let percentG = ((counterG / dna.length) * 100).toFixed(2);

      if (percentC >= 60 || percentG >= 60) {
        return true;
      } else {
        return false;
      }
    }
  }
}

let instance1 = pAequorFactory(1, mockUpStrand())
let instance2 = pAequorFactory(2, mockUpStrand())
const pAequorSet = [];

for (let i = 1; i <= 30; i++) {
  let instance = pAequorFactory(i, mockUpStrand())
  pAequorSet.push(instance);
}
 
instance1.mutate()

Challenge Project complete:
Mysterious Organism (Software Engineering Foundations)