D3 Examples - Bioinformatics Problems 2

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  <h1>Please look in the code below for 5 JavaScript practice problems.</h1>
  <p>(These problems don't include any SVG manipulation, so you will need to open the developer console in order to see the output of your code)</p>
  <script>
  // Problem 1: search array1 for those states whose location is "East"
  // using console.log(), print just the state name(s).
    console.log("Question 1")
  array1 = [
                    {name: "Arizona",  location: "Southwest"},
            {name: "Virginia", location: "East"},
            {name: "Florida",  location: "Southeast"}
           ];
​
    array1.forEach(function(e){
      if (e.location == "East"){
        console.log(e.name)
      }
    })
    
  // Problem 2: search array1 (above) for those states whose location contains the substring "South"
  // using console.log(), print just the state name(s) for these states.
    console.log("Question 2")
    
    array1.forEach(function(s){
      if (s.location.includes("South")){
        console.log(s.name)
      }
    })
    
   // console.log(array1)
    
  // Problem 3: using iteration and console.log(), print those items that are in
  // array2 but NOT in array3
    console.log("Question 3")
    
  array2 = ['a','b','c', 65, 'd'];
  array3 = ['a','c','e','f','g', 87];
    
    array2.forEach(function(a2){
      console.log(a2)
      if(array3.includes(a2) == false){
         console.log(array3.includes(a2))
         }
    })
    
   
  
  // Problem 4: 'states' is an array of objects. Sort the array in ascending order
  // by state name
    console.log("Question 4")
   
   
  states = [{name: "Alaska", id: "AK", population: 741894},
            {name: "Virginia", id: "VA", population: 8411808},
                    {name: "Arizona", id: "AZ", population: 6931071},
            {name: "Florida", id: "FL", population: 20984400}]
  
            states.sort(function(a,b){
          var nameA=a.name.toLowerCase(), nameB=b.name.toLowerCase()
            if(nameA < nameB)
              return -1
            if(nameA > nameB)
              return 1          
        })
        console.log(states)    
        
        //OR
        
        states.sort(function(a,b){
          return d3.ascending(a.name, b.name)
        })
        console.log(states)
        
        //OR
        
        states.sort(function(a,b){
          if(a.name < b.name){return -1}
          else if(a.name == b.name){return 0}
          else {return 1}
        })
        console.log(states)        
        
        
  // Problem 5: write code that determines which state(s) have a population value that is an even number. Print out the state(s) to the console
​
       console.log("Question 5")
        
       states.forEach(function(p){
         var pop=p.population
         if(pop % 2 == 0)
           console.log(p.name)
       })
       
       //OR
       
       states.forEach(function(s){
         console.log(s.name, s.population, s.population % 2==0)
         if(s.population % 2==0) {console.log(s)}
       })
      
  //MORE
       
        states2 = [{name: "Alaska", id: "AK", population: 741894},
            {name: "Virginia", id: "VA", population: 8411808},
                    {name: "Arizona", id: "AZ", population: 6931071},
            {name: "Florida", id: "FL", population: 20984400}] 
       
   // Problem 1: using d3.mean(), compute and print the average (mean) 
  // population of the states in the states array
  console.log("Question 1B")
        
      var popMean = d3.mean(states2, function(i){
         return i.population 
    })
       console.log(popMean)
  
  // Problem 2: WITHOUT using d3.mean(), compute and print the average (mean) 
  // population of the states in the states array
  console.log("Question 2B")
      
      var average=0;
        for(i=0; i < states2.length; i++){
       average += states2[i].population; 
      }
    average = average / states2.length;
    console.log(average)
    
    //OR
    
    var populations=0;
    var numberOfStates=0;
    states2.forEach(function(d){
      populations += d.population;
      numberOfStates++;
    })
    var mean = populations/numberOfStates;
    console.log(mean)
    
    //OR
    //???? not working...
    var populations2=0
    states2.forEach(function(d){
      populations2 += d.population;
      
      var mean2=populations2/states2.length;
      console.log("mean2", mean2)
    })
    
    //OR
    //Just kidding...
    
    var statesNumber
    var pop5
    while(pop5 in states2){
      statesNumber = statesNumber+1
      pop5 += d.population
    }
        var mean3 = pop5/states.length
      console.log("mean3", mean3)
    
      
    var pop4 = 0
    var mean4 = 0
    var i = 0
    while(i < states2.length){
        pop4 += states2[i].population;
      // += basically equals pop4 = pop4 + states2...
        i++;}
    mean4= pop4/states.length
    console.log("mean4", mean4)
      
  </script>
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