www.webdeveloper.com
Page 4 of 4 FirstFirst ... 234
Results 46 to 56 of 56

Thread: Ten Simple Javascript Exercises

  1. #46
    Join Date
    Dec 2009
    Posts
    1

    my solution,sorry i'm just a beginner

    I'm just a beginner,so regarding my solution to question 1,i've no idea whether it's correct or wrong,but hope any expert can correct and teach me(i just learn javascript last 2 weeks)

    <!-- Define a function max() that takes two numbers as arguments and returns the largest of them. Use the if-then-else construct available in Javascript.
    -->


    <html>
    <body>

    <script type="text/javascript">

    function max(firstNumber , secondNumber)
    {
    if (firstNumber > secondNumber)
    {
    document.write(firstNumber);
    }
    else if (isNaN(firstNumber) || isNaN(secondNumber))
    {
    document.write("You are not entering a number");
    }
    else
    {
    document.write(secondNumber);
    }
    }
    var firstNumber = parseFloat(prompt("Please enter your first number","")); <!-- the function parseFloat is use to prevent error when comparing negative number -->
    var secondNumber = parseFloat(prompt("Please enter your second number",""));
    max(firstNumber, secondNumber);

    </script>
    </body>
    </html>

  2. #47
    Join Date
    May 2011
    Posts
    8
    I know this is a REALLY old thread but Im going to add to it anyway. Attempting the OP's homework for him to teach myself and ran into a problem. The following code is the working solution to questions 1 & 2:

    ------------------------------------------------------
    <!--
    Define a function max() that takes two numbers as arguments and returns the largest of them. Use the if-then-else construct available in Javascript.
    -->

    <html><head><title>Some Guys Homework</title>
    <script type = "text/javascript">

    var num1 = 8;
    var num2 = 40;
    var num3 = 76;

    var maxNum = Math.max(num1, num2, num3);

    if (maxNum == num1) {
    alert(num1);
    }
    else if (maxNum == num2) {
    alert(num2);
    }
    else {
    alert(num3);
    }

    </script></head>
    <body>

    <p id = "maxField">&nbsp;</p>

    </body></html>
    -----------------------------------------

    This works fine but when I use the following code in place of the 3 alert(); in the if...else statement Firebug warns me that maxLoc is null.
    var maxLoc = document.getElementById("maxField");
    maxLoc.innerHTML = num1;

    it is not a syntax error because it runs fine if the if statement points to an alert(). I used the .innerHTML exaclty the same way before so Im confused. Any help?

  3. #48
    Join Date
    Dec 2003
    Location
    Bucharest, ROMANIA
    Posts
    15,428
    Quote Originally Posted by JohnnyCK View Post
    it is not a syntax error
    It is a syntax error, because the code runs before the element with the id="maxField" is loaded, so there is no element to be found at that time. Place the code within a function and call it onload
    Code:
    <script type = "text/javascript">
    function myFunction(){
    // the code here
    }
    onload=myFunction;
    </script>

  4. #49
    Join Date
    May 2011
    Posts
    8
    Works now. Thank You

  5. #50
    Join Date
    May 2011
    Posts
    8
    Working on another question now. Trying to simply print all the elements in an array.

    var vowelArray = new Array('a', 'e', 'i', 'o', 'u');

    for ( i=0; i < vowelArray.length; i++ ) {
    var createdVowelString = createdVowelString + vowelArray[i];
    }
    var vowelLoc = document.getElementById("vowelField");
    vowelLoc.innerHTML = createdVowelString;

    this works but prints undefined before the array. So "undefinedaeiou". I think undefined is because createdVowelString is originally undefined but if I assign it a value to begin with the loop only prints out the last letter in array 'u'. Like this:

    var createdVowelString = "";
    createdVowelString = createdVowelString + vowelArray[i];

  6. #51
    Join Date
    May 2011
    Posts
    8
    Just found array.toString is a much easier solution to my problem but if anyone sees why I got undefined I would still like to know so I understand better.

  7. #52
    Join Date
    Sep 2013
    Posts
    1
    I know OP had questionable motives, but I solved these questions. If anyone is interested in the answer,

    function max(x,y){
    if(x > y){
    return x;
    }
    else{
    return y;
    }
    }
    function max_of_three(x,y,z){
    var threes_company = [x,y,z];
    threes_company.sort();
    var howbig = threes_company.length;
    return threes_company[howbig - 1];
    }
    function vowel(c){
    var vowels = ['a','e','i','o','u'];
    if (vowels.indexOf(c) > -1){
    return true;
    }
    return false;
    }
    function translate(word){
    var translation = "";
    for (var x in word ){
    if(!vowel(word[x])){
    translation += word[x] + 'o' + word[x]
    }
    else{
    translation += word[x];
    }
    }
    return translation;
    }
    function sum(a){
    var the_sum = 0;
    for (var x in a){
    the_sum += a[x];
    }
    return the_sum;
    }
    function multiply(a){
    var the_product = 1;
    for (var x in a){
    the_product *= a[x];
    }
    return the_product;
    }
    function reverse(s){
    for(i = s.length - 1; i >= 0; i--){
    document.write(s[i]);
    }
    }
    function sort_alpha(a){
    a.sort();
    for (var x in a){
    document.write(a[x] + ' ');
    }
    }
    function findLongestWord(a){
    var longest = 0;
    for (var x in a){
    if (a[x].length > longest){
    longest = a[x].length;
    }
    }
    return longest;
    }
    function filterLongWords(a,i){
    var long_array = [];
    for (var x in a){
    if (a[x].length > i){
    long_array.push(a[x]);
    }
    }
    return long_array;
    }
    function charFreq(s){
    var frequencies = {};
    for (var x in s){
    if (typeof frequencies[s[x]] === 'undefined'){
    frequencies[s[x]] = 1;
    } else{
    frequencies[s[x]] += 1;
    }
    }
    return frequencies;
    }

  8. #53
    Join Date
    Aug 2013
    Posts
    3
    Here is an easier way;

    var num1 = prompt("Enter the first number: ", " ");
    var num2 = prompt("Enter the second number: ", " ");

    function max(){
    if(num1 > num2){
    document.write("The first number is the largest");
    }
    else{
    document.write("The second number is the largest");
    }
    }
    max();

  9. #54
    Join Date
    Aug 2013
    Posts
    3
    I thought this way was easier:

    var str = prompt("Enter a character: ", " ");
    var myVowels = ["a", "e", "i", "o", "u"];



    function testVowels(){
    if(str == myVowels[0]){
    if(str == myVowels[1]){
    if(str == myVowels[2]){
    if(str == myVowels[3]){
    if(str == myVowels[4]){
    }
    }
    }
    }
    document.write("True");
    console.log("True");
    console.log(str.length);
    }
    else{
    document.write("False");
    console.log("False");
    console.log(str.length);
    }
    }
    testVowels();

  10. #55
    Join Date
    Aug 2013
    Posts
    3
    Here is the second exercise:

    var num1 = prompt("Enter the first number: ", " ");
    var num2 = prompt("Enter the second number: ", " ");
    var num3 = prompt("Enter the third number: ", " ");

    function maxOfThree(){
    document.write("The largest number is: ", (Math.max(num1, num2, num3)));
    }
    maxOfThree();

  11. #56
    Join Date
    Apr 2014
    Location
    Dubai UAE
    Posts
    1
    Hi gays.........
    naw i just want to know because i want to learn stuff .

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
HTML5 Development Center



Recent Articles