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Javascript numbers - split/slice Prime

I am completely new to Javascript and trying to solve a simple problem now for more than two weeks and still not getting it(please help).
TASK ::::
Read a 4 digit Number e.g. 5678
Write a function
Split/separate the numbers and than build (5678, 567, 56, 5), than check if the numbers(5678, 567, 56, 5) are Prime numbers.
Give in Console/Result if 5678 a prime number or not, 567 a prime number or not and so on.
Check "if all numbers are Prime" than show result "All prime" if not show result "Not all prime".
Trying to solve the problem with (if else) but not really getting it, because i know very less about Javascript (arrays, string, split, slice) yet.
please help me understand. Thanks.
var a = 123456789;
var b = a.toString().length; //<<--->> ANTWORT: 9
document.write('ANTWORT: ',a );
for (i=0; i<b; i++) {
var x = a.toString().slice(0, -i);
document.write(x, ",");
}
function isPrime{
for(var i = 2; i < a; i++);
if(num % i === 0) return false;
return num > 1;
}

//integer is a string at the moment
integer = prompt("Enter a integer: ");
//initialize array for dictionary
dictArray = [];
stuff = document.getElementById("stuff");
//loop through all values of the string
for (var i = integer.length; i > 0; i--)
{
//take a substring from 0 to the ith char and turn it into an int
num = parseInt(integer.substring(0, i));
//add a dictionary to the array the tells what the number is
//and if it was prime or not as a bool
dictArray.push({"num": num, "prime": isprime(num)});
(dictArray[integer.length - i]["prime"]) ? stuff.innerHTML += "<br>" + num + " is prime." : stuff.innerHTML += "<br>" + num + " is not prime.";
}
function isprime(num)
{
if (num <= 3) return num >= 1;
if ((num % 2 === 0) || (num % 3 === 0)) return false;
let count = 5;
while (Math.pow(count, 2) <= num) {
if (num % count === 0 || num % (count + 2) === 0) return false;
count += 6;
}
return true;
}
//print the array
(dictArray.find(x => !x.prime) == undefined) ? stuff.innerHTML += "<br>All prime!" : stuff.innerHTML += "<br>Not all prime!";
//console.log(dictArray);
<div id="stuff">
</div>

Input number output corresponding value

Given these 9 words, display on the page the word corresponding to their chosen number
1.mercury
2.venus
3.earth
4.mars
5.jupiter
6.saturn
7.uranus
8.neptune
9.pluto
Im not sure what I'm missing here Ive done a lot of trial an error and nothing seems to work.
I've tried using numEntry as my comparison for all the if statements and it hasn't worked. When I made var numEntry = true; only Mercury would display. When I made var numEntry = 1,2,3,4,5,6,7,8,9 only pluto would show. I then tried to create a variable for each number and use each once in a comparison like below but every planet shows up instead of the corresponding number to planet.
var numberOfPlanet = prompt("Please enter a number between 1 and 9");
function thePlanets(){
var numOne = 1;
var numTwo = 2;
var numThree = 3;
var numFour = 4;
var numFive = 5;
var numSix = 6;
var numSeven = 7;
var numEight = 8;
var numNine = 9;
//do I need to define numberEntry if I use it in my comparisons below? what do I define it as after the = //// I tried defining as true but only mercury will appear, i tried inserting numbers 1 through 9 but only pluto worked//
if(numOne = 1 ){
document.write("mercury");
}
if(numTwo = 2 ){
document.write("venus");
}
if(numThree = 3 ){
document.write("earth");
}
if(numFour = 4 ){
document.write("mars");
}
if(numFive = 5 ){
document.write("jupiter");
}
if(numSix = 6 ){
document.write("saturn");
}
if(numSeven = 7 ){
document.write("uranus");
}
if(numEight = 8 ){
document.write("neptune");
}
if(numNine = 9 ){
document.write("pluto");
}
}
thePlanets();
I just need a number to correspond with the right planet when the user enters that number eg. ( user enters 1 and it displays mercury)

Some notes:
Use numberOfPlanet as the function argument to compare with (it becomes num inside the function).
Convert numberOfPlanet to Number as prompt() returns string.
Use === (strong comparison) instead of = (assignment).
Use else if instead of next if if you need only one variant from some so that the comparing stops when the right result is found.
var numberOfPlanet = Number(prompt("Please enter a number between 1 and 9"));
function thePlanets(num){
if(num === 1){
document.write("mercury");
}
else if(num === 2){
document.write("venus");
}
else if(num === 3){
document.write("earth");
}
else if(num === 4){
document.write("mars");
}
else if(num === 5){
document.write("jupiter");
}
else if(num === 6){
document.write("saturn");
}
else if(num === 7){
document.write("uranus");
}
else if(num === 8){
document.write("neptune");
}
else if(num === 9){
document.write("pluto");
}
}
thePlanets(numberOfPlanet);

JavaScript: formatting input method gives wrong values

I'm programming a method in JavaScript/JQuery which converts the value an user enters in an inputbox. The meaning is to make this input regional aware.
The functionality contains removing zeros at the beginning, placing thousand seperators and a decimal separator.
In this use case is the , symbol a thousand separator and the . dot the decimal separator
For example following input gets converted in following output.
12300 => 12,300.00
100 => 100.00
1023.456 => 1,023.456
Now There is still a problem with numbers, less than 100.
For example following input is malformed:
1 => 1,.00
2.05 => .05
20 => 20,.00
25.65 => .65
When I don't enter a decimal value in the input box, I get an unneeded thousand separator. When I enter a decimal value, I lose my content before the decimal separator.
The code:
$("#queryInstructedAmountFrom").change(function(){
var amount = $("#queryInstructedAmountFrom").val();
amount = removeZeros(amount);
var nonFractions = amount.match(/.{1,3}/g);
if(nonFractions == null) {
nonFractions = [];
nonFractions.push(amount);
}
var splittedValues = amount.split(/[,.]/);
amount = "";
if(splittedValues.length == 1) {
amount += splittedValues[0];
nonFractions = amount.match(/.{1,3}/g);
var firstIndex = amount.length % 3;
if(firstIndex != 0) {
var firstNumbers = amount.substr(0, firstIndex);
amount = amount.substr(firstIndex);
nonFractions = amount.match(/.{1,3}/g);
if(nonFractions == null) {
nonFractions = [];
nonFractions.push(amount);
}
amount = "";
amount += firstNumbers;
amount += thousandSeparator;
} else {
amount = "";
}
for(var i=0 ; i < nonFractions.length ; i++) {
amount += nonFractions[i];
if(i < (nonFractions.length - 1) && nonFractions.length != 1){
amount += thousandSeparator;
}
}
amount += decimalSeparator;
amount += "00";
} else {
for(var i=0 ; i < splittedValues.length - 1 ; i++) {
amount += splittedValues[i];
}
nonFractions = amount.match(/.{1,3}/g);
var firstIndex = amount.length % 3;
if(firstIndex == 0) {
nonFractions = amount.match(/.{1,3}/g);
}
if(firstIndex >= 1 && nonFractions != null) {
var firstNumbers = amount.substr(0, firstIndex);
amount = amount.substr(firstIndex);
nonFractions = amount.match(/.{1,3}/g);
if(nonFractions != null) {
amount = "";
amount += firstNumbers;
amount += thousandSeparator;
} else {
nonFractions = [];
nonFractions.push(amount);
}
} else {
amount = "";
}
for(var i=0 ; i < nonFractions.length ; i++) {
amount += nonFractions[i];
if(i < (nonFractions.length - 1) && nonFractions.length != 1){
amount += thousandSeparator;
}
}
amount += decimalSeparator;
amount += splittedValues[splittedValues.length -1];
}
$("#queryInstructedAmountFrom").val(amount);
});
});
function removeZeros(amount) {
while (amount.charAt(0) === '0') {
amount = amount.substr(1);
}
if(amount.length == 0){
amount = "0";
}
return amount;
}
What is going wrong?

What is going wrong?
I'd say almost everything. You have very unclear, messy code, I hardly following your logic, but you have several critical logic mistakes in code, for example:
1
1 is converted to 1,.00 because:
var splittedValues = amount.split(/[,.]/);
creates array with single element ['1']
var firstIndex = amount.length % 3;
1%3 == 1, so you're going into if condition, where amount += thousandSeparator; appends thousand separator, but you should add separator only if you have something after that
2
2.05 is wrong, because it goes into this branch:
var firstNumbers = amount.substr(0, firstIndex); // stores '2' into firstNumbers
amount = amount.substr(firstIndex); // sets amount to empty string
later, nonFractions is null:
nonFractions = [];
nonFractions.push(amount);
but firstNumbers is not used at all, ie its value is lost
3
also, you have:
nonFractions = amount.match(/.{1,3}/g);
var firstIndex = amount.length % 3;
if (firstIndex == 0) {
nonFractions = amount.match(/.{1,3}/g);
}
what is the sense of nonFractions re-init?
probably there are more errors and edge cases where this code fails, I suggest you to use library (like in other answers) or if you want to have your own code, here is simple version you can use:
$(document).ready(function() {
$("#queryInstructedAmountFrom").change(function() {
var val = parseFloat(('0' + $("#queryInstructedAmountFrom").val()).replace(/,/g, '')); // convert original text value into float
val = ('' + (Math.round(val * 100.0) / 100.0)).split('.', 2);
if (val.length < 2) val[1] = '00'; // handle fractional part
else while (val[1].length < 2) val[1] += '0';
var t = 0;
while ((val[0].length - t) > 3) { // append thousand separators
val[0] = val[0].substr(0, val[0].length - t - 3) + ',' + val[0].substr(val[0].length - t - 3);
t += 4;
}
$("#queryInstructedAmountFrom").val(val[0] + '.' + val[1]);
});
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<input type="text" id="queryInstructedAmountFrom">

Why don't you use jQuery-Mask-Plugin?
<input type="text" id="money" />
and just invoke the plugin:
$('#money').mask('000.000.000.000.000,00', {reverse: true});
Plunker: https://plnkr.co/edit/PY7ihpS3Amtzeya9c6KN?p=preview

Refer to the below code updated.
$(document).ready(function() {
$("#queryInstructedAmountFrom").change(function() {
var amount = $("#queryInstructedAmountFrom").val();
amount = removeZeros(amount);
// format amount using 'ThousandFormattedValue' function
amount = ThousandFormattedValue(amount);
$("#queryInstructedAmountFrom").val(amount);
});
});
function removeZeros(amount) {
while (amount.charAt(0) === '0') {
amount = amount.substr(1);
}
if (amount.length == 0) {
amount = "0";
}
return amount;
}
function ThousandFormattedValue(iValue) {
// declaring variables and initializing the values
var numberArray, integerPart, reversedInteger, IntegerConstruction = "",
lengthOfInteger, iStart = 0;
// splitting number at decimal point by converting the number to string
numberArray = iValue.toString().split(".");
// get the integer part
integerPart = numberArray[0];
// get the length of the number
lengthOfInteger = integerPart.length;
// if no decimal part is present then add 00 after decimal point
if (numberArray[1] === undefined) {
numberArray.push("00");
}
/* split the integer part of number to individual digits and reverse the number
["4" , "3" , "2" , "1"] - after split
["1" , "2" , "3" , "4"] - after reverse
"1234" - after join
*/
reversedInteger = integerPart.split("").reverse().join("");
// loop through the string to add commas in between
while (iStart + 3 < lengthOfInteger) {
// get substring of very 3 digits and add "," at the end
IntegerConstruction += (reversedInteger.substr(iStart, 3) + ",");
// increase counter for next 3 digits
iStart += 3;
}
// after adding the commas add the remaining digits
IntegerConstruction += reversedInteger.substr(iStart, 3);
/* now split the constructed string and reverse the array followed by joining to get the formatted number
["1" , "2" , "3" , "," ,"4"] - after split
["4" , "," , "3" , "2" , "1"] - after reverse
"4,321" - after join
*/
numberArray[0] = IntegerConstruction.split("").reverse().join("");
// return the string as Integer part concatinated with decimal part
return numberArray.join(".");
}

How to use Javascript math on a version number

I use jQuery to get the browser version like this:
var x = $.browser.version;
I get a string like this: 1.9.1.1
Now, I want to do an evaluation so if x is >= 1.9.1 then do some stuff. Unfortunately, with multiple decimal points, I cannot do a parseFloat() because it converts 1.9.1.1 to simply 1.9, and the if evaluation would match a 1.9.0 version (which I do not want).
Has someone figured out a way to accomplish turning a version number (with multiple decimals) into something that can be used as a number for evaluation (or some other way to accomplish what I am trying to do here)?
Thanks -

You could do something with string.split and then do a digit by digit comparison
// arr[0] = 1
// arr[1] = 9
// arr[2] = 1
// arr[3] = 1
var arr = ($.browser.version).split('.');
The following is taken from this post
This is a function that will parse your version string and give you back a JSON object
function parseVersionString (str) {
if (typeof(str) != 'string') { return false; }
var x = str.split('.');
// parse from string or default to 0 if can't parse
var maj = parseInt(x[0]) || 0;
var min = parseInt(x[1]) || 0;
var bld = parseInt(x[2]) || 0;
var rev = parseInt(x[3]) || 0;
return {
major: maj,
minor: min,
build: bld,
revision: rev
}
}
Then you could use the following syntax
var version = parseVersionString($.browser.version);
// version.major == 1
// version.minor == 9
// version.build == 1
// version.revision == 1

Here's another version of versionCmp():
function versionCmp(v1, v2) {
v1 = String(v1).split('.');
v2 = String(v2).split('.');
var diff = 0;
while((v1.length || v2.length) && !diff)
diff = (+v1.shift() || 0) - (+v2.shift() || 0);
return (diff > 0) - (diff < 0);
}
Another possibility would be to assign a numeric value to each version number:
function valueOfVersion(ver) {
ver = String(ver).split('.');
var value = 0;
for(var i = ver.length; i--;)
value += ver[i] / Math.pow(2, i * 8) || 0;
return value;
}
This only works if each digit is less than 256 (because of the hard-coded divisor) and has a limited precision (ie the version strings can't get arbitrarily long).

You need to treat each portion of the string as a seperate integer, so split and iterate, and cmp:
// perform cmp(a, b)
// -1 = a is smaller
// 0 = equal
// 1 = a is bigger
function versionCmp(a, b) {
a = a.split(".");
b = b.split(".");
for(var i=0; i < a.length; i++) {
av = parseInt(a[i]);
bv = parseInt(b[i]);
if (av < bv) {
return -1;
} else if (av > bv) {
return 1;
}
}
return 0;
}
console.log(versionCmp("1.1.2.3", "1.2.1.0")); // should be -1
console.log(versionCmp("1.19.0.1", "1.2.0.4")); // should be 1
console.log(versionCmp("1.2.3.4", "1.2.3.4")); // should be 0

You could remove all dots and then parse it as an integer.
Take note tho, this solution doesn't work in the long term.

How to format numbers in JavaScript?

How to format numbers in JavaScript?
JavaScript culture sensitive currency formatting

The best you have with JavaScript is toFixed() and toPrecision() functions on your numbers.
var num = 10;
var result = num.toFixed(2); // result will equal 10.00
num = 930.9805;
result = num.toFixed(3); // result will equal 930.981
num = 500.2349;
result = num.toPrecision(4); // result will equal 500.2
num = 5000.2349;
result = num.toPrecision(4); // result will equal 5000
num = 555.55;
result = num.toPrecision(2); // result will equal 5.6e+2
Currency, commas, and other formats will have to be either done by you or a third party library.

The improved script (the previous was buggy, sorry; to be honest I haven't tested this exaustively either), it works like php number_format:
function formatFloat(num,casasDec,sepDecimal,sepMilhar) {
if (num < 0)
{
num = -num;
sinal = -1;
} else
sinal = 1;
var resposta = "";
var part = "";
if (num != Math.floor(num)) // decimal values present
{
part = Math.round((num-Math.floor(num))*Math.pow(10,casasDec)).toString(); // transforms decimal part into integer (rounded)
while (part.length < casasDec)
part = '0'+part;
if (casasDec > 0)
{
resposta = sepDecimal+part;
num = Math.floor(num);
} else
num = Math.round(num);
} // end of decimal part
while (num > 0) // integer part
{
part = (num - Math.floor(num/1000)*1000).toString(); // part = three less significant digits
num = Math.floor(num/1000);
if (num > 0)
while (part.length < 3) // 123.023.123 if sepMilhar = '.'
part = '0'+part; // 023
resposta = part+resposta;
if (num > 0)
resposta = sepMilhar+resposta;
}
if (sinal < 0)
resposta = '-'+resposta;
return resposta;
}