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 stand of DNA containing 15 bases
  const mockUpStrand = () => {
    const newStrand = []
    for (let i = 0; i < 15; i++) {
      newStrand.push(returnRandBase())
    }
    return newStrand
  }
  
  const pAequorFactory = (nr, dnaArray) => {
    return {
      specimenNum: nr,
      dna: dnaArray,
      mutate() {
        const dnaBases = ['A', 'T', 'C', 'G'];
        const randIndex = Math.floor(Math.random() * 15);
        const selectedBase = this.dna[randIndex];
        const newBases = dnaBases.filter(base => base !== selectedBase);
        this.dna[randIndex] = newBases[Math.floor(Math.random() * 3)];
        return this.dna;
      },
      compareDNA(pAequor) {
        const ex1 = this.dna;
        const ex2 = pAequor.dna;
        let sameBases = 0;
        for (let i = 0; i < ex1.length; i++) {
          if (ex1[i] === ex2[i]) {
            sameBases++;
          }
        }
        const percentageSame = Math.round((sameBases / 15) * 100);
        console.log(`Speciment #${this.specimenNum} and #${pAequor.specimenNum} have ${percentageSame}% DNA in common.`);
      },
      willLikelySurvive() {
          const cgArray = this.dna.filter(base => base === 'C' || base === "G");
          return (cgArray.length / 15) >= 0.6 ? true : false; 
      }
    }
  }
  
let surviveNr = 1;
let pAequorArray = [];
while (surviveNr <= 30) {
    const newPAequor = pAequorFactory(surviveNr, mockUpStrand());
    if (newPAequor.willLikelySurvive()) {
        pAequorArray.push(newPAequor);
        surviveNr++;
    }
}

//Tests
console.log('Length should be 30. Result: ' + pAequorArray.length);
console.log('Array of specimens:');
pAequorArray.forEach(specimen => console.log(specimen.dna));
console.log('Percentage of C/G in each specimen: ');
pAequorArray.forEach(specimen => {
    const cgArray = specimen.dna.filter(base => base === 'C' || base === 'G');
    const percentageCG = Math.round((cgArray.length / 15) * 100);
    console.log(`Strand: ${specimen.specimenNum} Percentage C/G: ${percentageCG}`);
})