Loop function not working for vowel counter. How can i make a counter text bold

Question

My loop function for my vowels counter in not working correctly and I don't know where I have gone wrong I would like some assistance with it.

I am trying to get the most used vowel to be bold so say I have A = 34 and E = 45 so E should be bold like this E

But I don't know whether I am missing some code or if I have got something wrong in my code.

This is my JavaScript.

 function countVowels() {

     var text = document.getElementById("text").value;

     var arrayOfLetters = text.split("");

     // These are the counters for the program to find the vowels.
     var countA = text.match(/[Aa]/g).length;
     var countE = text.match(/[Ee]/g).length;
     var countI = text.match(/[Ii]/g).length;
     var countO = text.match(/[Oo]/g).length;
     var countU = text.match(/[Uu]/g).length;
     var countComma = text.match(/[,.!": ;?)(]/g).length;

     var bold = "<strong>";
     var vowels = new Array();
     vowels[0] = "countA";
     vowels[1] = "countE";
     vowels[2] = "countI";
     vowels[3] = "countO";
     vowels[4] = "countU";

     for (var i = 0; i < vowels.length; i++) {
         document.getElementById("result").innerHTML = i + vowels[i] + "<br />";

     }
     // This code will output the results.
     document.getElementById("result").innerHTML = "";
     document.getElementById("result").innerHTML += "Total Letters: " + arrayOfLetters.length + "<br />";
     document.getElementById("result").innerHTML += "A's: " + countA + "<br />";
     document.getElementById("result").innerHTML += "E's: " + countE + "<br />";
     document.getElementById("result").innerHTML += "I's: " + countI + "<br />";
     document.getElementById("result").innerHTML += "O's: " + countO + "<br />";
     document.getElementById("result").innerHTML += "U's: " + countU + "<br />";
     document.getElementById("result").innerHTML += "Punctuation: " + countComma + "<br />";
 }

This is my HTML.

<div style="text-align: center;">
    <h1> Vowel Counter </h1>
    Please enter text for your vowel count:
    <br>
    <textarea id="text" rows="10" style="width: 100%;"></textarea>
    <br>
    <button onclick="countVowels();">Count Vowels</button>
    <p id="result"></p>

And this is my fiddle .

Answer 1

var result = "";
for(var i = 0; i < text.length ; i++){
 if(text[i] == vowelsmustusedUpCase || text[i] == vowelsmustusedLowCase ){
  result += "<strong>"+text[i]+"</strong>";
 } else {
  result += text[i];
 }
} 
document.getElementById("text").value = result ;

add this, but in textarea you can't see the bold

Answer 2

Ok here's a code review/answer:

First I modified these lines:

var countA = text.match(/[Aa]/g).length;

To:

var countA = (text.match(/[Aa]/g) ? text.match(/[Aa]/g).length : 0);

As it returns " Uncaught TypeError: Cannot read property 'length' of null " if the vowel doesn't appear in the control. This will set's it to 0.

Next I simplified the array declaration to:

var vowels = ["countA", "countE", "countI", "countO", "countU"];

Then I removed this seciton, which does nothing as it's overwritten later:

// does nothing
//    for (var i = 0; i < vowels.length; i++) {
//       document.getElementById("result").innerHTML = i + vowels[i] + "<br />";
//    }

Then I worked out the highest count using Math.max :

var maxVal = Math.max(countA,countE,countI,countO,countU);

Then to make the value bold in the output, I created a function to compare values to the max value:

function formatValue(val, max) {
    return (val === max) ? '<strong>' + val + '</strong>' : val;
}

So your final section would call this function to output the number like this:

document.getElementById("result").innerHTML += "A's: " + formatValue(countA,maxVal) + "<br />";

Demo JS Fiddle

Complete JS

function countVowels() {

    var text = document.getElementById("text").value;
    var arrayOfLetters = text.split("");

    // These are the counters for the program to find the vowels.
    var countA = (text.match(/[Aa]/g) ? text.match(/[Aa]/g).length : 0);
    var countE = (text.match(/[Ee]/g) ? text.match(/[Ee]/g).length : 0);
    var countI = (text.match(/[Ii]/g) ? text.match(/[Ii]/g).length : 0);
    var countO = (text.match(/[Oo]/g) ? text.match(/[Oo]/g).length : 0);
    var countU = (text.match(/[Uu]/g) ? text.match(/[Uu]/g).length : 0);
    var countComma = (text.match(/[,.!": ;?)(]/gi) ? text.match(/[,.!": ;?)(]/gi).length : 0);

    var bold = "<strong>";
    var vowels = ["countA", "countE", "countI", "countO", "countU"];       
    var maxVal = Math.max(countA,countE,countI,countO,countU);

    // This code will output the results.
    document.getElementById("result").innerHTML = "";
    document.getElementById("result").innerHTML += "Total Letters: " + arrayOfLetters.length + "<br />";
    document.getElementById("result").innerHTML += "A's: " + formatValue(countA,maxVal) + "<br />";
    document.getElementById("result").innerHTML += "E's: " + formatValue(countE,maxVal) + "<br />";
    document.getElementById("result").innerHTML += "I's: " + formatValue(countI,maxVal) + "<br />";
    document.getElementById("result").innerHTML += "O's: " + formatValue(countO,maxVal) + "<br />";
    document.getElementById("result").innerHTML += "U's: " + formatValue(countU,maxVal) + "<br />";
    document.getElementById("result").innerHTML += "Punctuation: " + countComma + "<br />";
}

function formatValue(val, max) {
    return (val === max) ? '<strong>' + val + '</strong>' : val;
}

Answer 3

I think you should first find which is the most used vowel, and then compare it with the result line in your output. Eg:

vowelCount = { A: countA, E: countE, I: countI, O:countO, U:countU };

// Find vowel with maximum appearances
var vowelMaxCount = -1;
var vowelMostPopular = -1;
for(vowel in vowelCount) {
    if(vowelCount[vowel] > vowelMaxCount) {
        vowelMaxCount = vowelCount[vowel];
        vowelMostPopular = vowel;
    }
}

// This code will output the results.
document.getElementById("result").innerHTML = "";
document.getElementById("result").innerHTML += "Total Letters: " + arrayOfLetters.length + "<br />";
for(vowel in vowelCount) {
    v = (vowel == vowelMostPopular)?"<strong>"+vowel+"</strong>":vowel;
    document.getElementById("result").innerHTML += v+"'s: " + vowelCount[vowel] + "<br />";
}
document.getElementById("result").innerHTML += "Punctuation: " + countComma + "<br />";

Demo fiddle: http://jsfiddle.net/lparcerisa/a8n947kw/1/

Answer 4

You seem to be getting the count right. So the only problems left I guess are:

1. Getting max count
2. Displaying it in bold

I referred to this to get max count, and then some tweaks to your code to get the max count displayed in bold.

var vowels = new Array ();
vowels [0] = {"vowel" : "A", "count" : countA};
vowels [1] = {"vowel" : "E", "count" : countE};
vowels [2] = {"vowel" : "I", "count" : countI};
vowels [3] = {"vowel" : "O", "count" : countO};
vowels [4] = {"vowel" : "U", "count" : countU};
var maxCount = Math.max.apply(Math, vowels.map(function(o) {
    return o.count;
}));

for (var i = 0; i < vowels.length; i++) {
    document.getElementById("result").innerHTML += (vowels[i].count == maxCount? "<B>" : "") + vowels[i].vowel + "'s: " + vowels[i].count + "<br />";
}

See this updated fiddle .