Codecademy Mysterious Organism Project

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 = (num,arr) => { //factory function for new strand specimen
  return {
    specimenNum: num,
    dna: arr,
    mutate () {
      //console.log(`old dna: ${this.dna}`) //checking log
      let randomBaseIndex = Math.floor(Math.random() * this.dna.length) /// chooses a location to exchange the base
      let newBase = returnRandBase()
      while (newBase === this.dna[randomBaseIndex]) { // Rolls a new base until newBase !== current base at that position
        newBase = returnRandBase()
      }
      this.dna[randomBaseIndex] = newBase;
      //console.log(`New dna: ${this.dna}`) //checking log
      return this.dna;
    },
    compareDNA(pAequor) { // compare two strands and output to the console
      let thisDNA = this.dna; 
      let compDNA = pAequor.dna;
      let matchCount = 0
      for (i = 0; i < this.dna.length; i++) { //cycles through each array and log position + base matches on matchCount
        if (thisDNA[i] === compDNA[i]) {
          matchCount += 1;
        };
      };
      let percMatch = Math.round(matchCount / this.dna.length * 100) //multiply by 100 to make 0.25 display as 25 in console log
      console.log(`specimen #${this.specimenNum} and specimen #${pAequor.specimenNum} are a ${percMatch}% DNA match.`)
      return percMatch;
    },
    compareDNAbulk(pAequor) { //as above, but does not log to console. Used for large arrays in findMostRelated()
      let thisDNA = this.dna;
      let compDNA = pAequor.dna;
      let matchCount = 0
      for (i = 0; i < this.dna.length; i++) {
        if (thisDNA[i] === compDNA[i]) {
          matchCount += 1;
        };
      };
      let percMatch = Math.round(matchCount / this.dna.length * 100) //multiply by 100 to make 0.25 display as 25 in console log
      return percMatch;
    },
    willLikelySurvive() { // looks for >= 60% of bases as either G or C
      let countCG = 0;
      this.dna.forEach(base => {
        if (base === 'C' || base ==='G') {
          countCG +=1;
        }
      })
      //console.log(countCG) // testing
      //console.log(this.dna) // testing
      return countCG / this.dna.length >= 0.6
    },
    complementStrand() {
      return this.dna.map(base => {
        switch (base) {
          case 'A' :
          return 'T';
          case 'T' :
          return 'A';
          case 'C' :
          return 'G';
          case 'G' :
          return 'C';
        }
      })
    } //close method
  } // close object
} // close factory function

function generatepAequorArray(num) { // Generatess 'num' pAequor that .willLikelySurvive() = true
  let pAequorArray = []; //result array
  for (i = 0; pAequorArray.length < num; i++) {
    let newpAequor = pAequorFactory(i,mockUpStrand()); // runs factory until there are 30 items in the result array
    if (newpAequor.willLikelySurvive() === true) {
      pAequorArray.push(newpAequor)
    }
  }
  return pAequorArray;
}

function findMostRelated (array) { // champion/challenger function to find the most related specimens
  let winningScore = 0;
  let winner1;
  let winner2;
  for (let i = 0; i < array.length; i++) {
    for ( let j = i; j < array.length; j++) // j = i to halve the number of loops. i = 0, j = 5 is the same as i = 5, j = 0
    if (i !== j) { // Do not check specimen against itself
      let currentScore = array[i].compareDNAbulk(array[j]);
      if (currentScore > winningScore) { // Challenger becomes the champion if they are a closer match
        winningScore = currentScore;
        winner1 = array[i].specimenNum;
        winner2 = array[j].specimenNum;
      }
    }
  }
  
  let resultArray = [winner1,winner2,winningScore] // stored together for easy return
  //console.log(`The most related specimens are specimen #${winner1} and specimen #${winner2}, with a ${winningScore}% match.`)
  return resultArray
} 



function multiArray (loops) { //test by running finding the closest match in 30 random 'will survive' samples, repaeated 1000 times. Returns the highest and lowest match across the 1000 runs
  let highScore = 0;
  let lowScore = 100
  for (let i = 0; i < loops; i++) {
    let pAequorArray = generatepAequorArray(30);
    let currentArray = findMostRelated(pAequorArray);
    highScore = Math.max(highScore,currentArray[2])
    lowScore = Math.min(lowScore,currentArray[2])
  }
  return results = {
    'high score' : highScore,
    'low score' : lowScore
  }
}


// All code called below this line
console.log(multiArray(1000))

/*
const pAequor1 = pAequorFactory(1,mockUpStrand())
const arr1 = pAequor1.complementStrand()
const pAequor2 = pAequorFactory(2,arr1)

console.log(pAequor1.willLikelySurvive()) // ran the code a few times until this read 'true'
pAequor1.compareDNA(pAequor2) //0%!

console.log(pAequor1)
console.log(pAequor2)
*/