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Issues with using negative numbers in a prompt box

Very new to JavaScript, the first programming language I learned was Java. I am trying to make a simple website that displays the shortest distance between an infinite number of points using prompt boxes and a 2D array.
This code works as expected, however when one of the points has a negative number in it, nothing ever displays for an answer, throwing the error:
Uncaught TypeError: Cannot read property '0' of undefined
at run (index.html:54)
at HTMLButtonElement.onclick (index.html:63)
Google Chrome highlights the error at this line:
toRun = "Shortest distance is " + min + " with these points: (" + finalPoints[0][0] + ", " + finalPoints[1][0] + ") and (" + finalPoints[0][1] + ", " + finalPoints[1][1] + ").";
How can I get this program to work with negative numbers as well?
function run() {
var x, y;
var finalPoints = [];
var min = 0;
var toRun;
var temp;
var list = []; //using 2d array to store points
while (true) {
x = prompt("Enter an X-Value: ");
if (x == null || x == "") {
break;
}
y = prompt("Enter a Y-Value: ");
if (y == null || y == "") {
break;
}
list.push([x, y]);
}
if (list.length < 2) {
toRun = "Sorry, you didn't enter enough points for this program to run correctly. Please try again.";
} else if (list.length == 2) {
toRun = "Distance between points (" + list[0][0] + ", " + list[0][1] + ") and (" + list[1][0] + ", " + list[1][1] + ") is " + Math.sqrt(Math.pow((list[0][0] - list[1][0]), 2) + Math.pow((list[0][1] - list[1][1]), 2));
} else {
min = Math.sqrt(Math.pow((list[0][0] - list[1][0]), 2) + Math.pow((list[0][1] - list[1][1]), 2));
for (var i = 0; i < list.length; i++) {
for (var j = 0; j < list.length; j++) {
temp = Math.sqrt(Math.pow((list[i][0] - list[j][0]), 2) + Math.pow((list[i][1] - list[j][1]), 2));
if (temp < min && temp != 0) {
min = temp;
finalPoints.push([list[i][0], list[j][0]]);
finalPoints.push([list[i][1], list[j][1]]);
}
}
}
toRun = "Shortest distance is " + min + " with these points: (" + finalPoints[0][0] + ", " + finalPoints[1][0] + ") and (" + finalPoints[0][1] + ", " + finalPoints[1][1] + ").";
}
document.getElementById("output").innerHTML = toRun;
}
body {
background-color: #0d0d0d;
}
p,
button,
h3 {
color: #FFFFFF;
background-color: #0d0d0d;
}
button {
border: 1px solid #FFFFFF;
}
<h3>Continue entering points. When done, click cancel or don't enter anything.</h3>
<br>
<button onclick="run()" style="size:40%">Click me to start!</button>
<p id=output>(Output will display here).</p>

Object.keys(arr).reduce() returns undefined

I am creating an object from an array like so
var val = $(this).val();
var type = " " + $("#backing").val() + " ";
var arr = $.extend({}, comb_arr[type]);
The result
var arr = {"1-4 ": "$10.10 ", "5-9 ": "$8.34 ", "10-24 ": "$7.71 ", "25-49 ": "$7.21 "}
When I run the below code through the output is undefined
var price = Object.keys(arr).reduce((a, c) => {
var s = c.trim();
if(/\d+\-\d+/.test(s)){
var range = s.split("-");
if(val >= parseInt(range[0]) && val <= parseInt(range[1])){
a = comb_arr[c];
}
}else{
s = s.replace(/\D/g, "");
if(val >= s){
a = comb_arr[c];
}
}
return a;
},0);
All ideas are welcome!

I am currently stuck on how to display this array

This is the code I currently have. I am having issues displaying the ordinals as I am not sure what for loop to put then in. Can someone please assist?
var bandsString = "";
var newBandString = "";
var bandsListArray = ["Linkin Park", "Atmosphere", "Rage Against The Machine", "Immortal Technique", "System of a Down"];
for (var i = 0; i < bandsListArray.length; i++) {
var currentBand = bandsListArray[i];
bandsString += "<li> My #" + [i + 1] + " band is " + currentBand + "</li>";
}
var bands = i;
if (bands == 0) {
bands = i + "st";;
} else if (bands == 1) {
bands = i + "nd";
} else if (bands == 2) {
bands = i + "rd";
} else if (bands == 3) {
bands = i + "th";
} else if (bands == 4) {
bands = i + "th";
} else {
}
for (var i = 0; i < bandsListArray.length; i++) {
var newBandList = bandsListArray[i];
newBandString += "<li>My # " + [i + 1] + " band is " + currentBand + "</li>";
}
document.write(bandsString);
document.write(newBandString);

I'm not exactly sure what you're trying to do, but does this help? Instead of manually working out how to put the correct ordinal suffix ('st', 'nd', 'rd', etc.) on the numbers, I googled a function.
The ordinal_suffix_of function works like this:
This first part is the start of the function. Hopefully this is self-explanatory. We're creating a function that accepts one parameter, that will be named i inside the function.
function ordinal_suffix_of(i) {
This next part defines j and k. You can declare multiple variables while only typing var once by using commas, as this code does:
var j = i % 10,
k = i % 100;
This would do exactly the same thing:
var j = i % 10;
var k = i % 100;
The percent sign (%) is called "modulus" and is a mathematical operator. What it does is divide the left operand by the right operand and returns the remainder. So in the case of j, it's being assigned remainder of dividing i by 10. If i was 14, for example, j would be 4. If i was 179, j would be 9. The same thing happens for k except that it's divided by 100 instead of 10.
What it's effectively doing is extracting the last 1 digit (for j) and the last 2 digits (for k) and then just checking (in the if statements) what ordinal suffixes they should have.
The reason for k is that you always want numbers ending in 1, 2, or 3 to have the suffixes st, nd , and rd except when the number ends in 11, 12, or 13, in which case it should get the suffix th. So for example, 112 should be 112th, and 313513 should be 313513th. k handles this by making it so that if the number ends in 11, 12, or 13 we only add th. Note that 11 % 100 will result in 11, so this works for 11, 12, and 13 as well.
var bandsString = "";
var newBandString = "";
var bandsListArray = ["Linkin Park", "Atmosphere", "Rage Against The Machine", "Immortal Technique", "System of a Down"];
for (var i = 0; i < bandsListArray.length; i++) {
var currentBand = bandsListArray[i];
bandsString += "<li> My #" + (i + 1) + " band is " + currentBand + "</li>";
}
for (var i = 0; i < bandsListArray.length; i++) {
var newBandList = bandsListArray[i];
newBandString += "<li>My " + ordinal_suffix_of(i + 1) + " band is " + newBandList + "</li>";
}
function ordinal_suffix_of(i) {
var j = i % 10,
k = i % 100;
if (j == 1 && k != 11) {
return i + "st";
}
if (j == 2 && k != 12) {
return i + "nd";
}
if (j == 3 && k != 13) {
return i + "rd";
}
return i + "th";
}
document.write(bandsString);
document.write(newBandString);

Try this, just make the code more simple
var bandsString = "";
var newBandString = "";
var bandsListArray = ["Linkin Park", "Atmosphere", "Rage Against The Machine", "Immortal Technique", "System of a Down"];
for (var i = 0; i < bandsListArray.length; i++) {
var currentBand = bandsListArray[i];
bandsString += "<li> My #" + [i + 1] + " band is " + currentBand + "</li>";
newBandString += "<li> My #" + numeric(i+1) + " band is " + currentBand + "</li>";
}
function numeric(i){
var bands = i+"th";
if (i == 1) {
bands = i + "st";;
} else if (i == 2) {
bands = i + "nd";
} else if (i == 3) {
bands = i + "rd";
}
return bands;
}
document.write(bandsString);
document.write(newBandString);

If this is what you are trying to achieve is:
My 2nd band is Atmosphere
Then this how you might achieve it
var bandsString = "";
var newBandString = "";
var bandsListArray = ["Linkin Park", "Atmosphere", "Rage Against The Machine", "Immortal Technique", "System of a Down"];
for (var i = 0; i < bandsListArray.length; i++) {
var currentBand = bandsListArray[i];
bandsString += "<li> My #" + (i + 1) + " band is " + currentBand + "</li>";
newBandString += "<li>My " + numberSuffix(i + 1) + " band is " + currentBand + "</li>";
}
function numberSuffix(number){
if(number % 10==1) return number+'st';
if(number % 10==2) return number+'nd';
if(number % 10==3) return number+'rd';
return number+'th';
}
document.write(bandsString);
document.write(newBandString);

change the text of a label and in js and use it from code behind?

I created a list of buttons from code behind, and append them on some div, how ever each button has an onclick java script function
here is how I did it:
string[] messages = CM.GetMessages(Session["USER_EMAIL"].ToString()).Split(new string[] { "$STARTCHAT$" }, StringSplitOptions.None);
string[] usersalone = CM.GetChaters(Session["USER_EMAIL"].ToString()).Split(new string[] { "$NEWUSER$" }, StringSplitOptions.None);
string[] username = CM.GetUserNames(Session["USER_EMAIL"].ToString()).Split(new string[] { "$NEWUSER$" }, StringSplitOptions.None);
for (int i = messages.Length-2; i>=0; i--)
{
Button b = new Button();
b.ID = Session["USER_EMAIL"].ToString()+username[i];
b.Text = "Chat With: " + usersalone[i] ;
b.Width = 250;
b.Height = 100;
b.OnClientClick = "return DisplayMessage('" + messages[i+1] + "','" + username[i] + "','" + Session["USER_EMAIL"].ToString() + "')";
b.Style.Add("background-color", "rgb(246, 246, 246)");
// lblChatwith.Text = username[i];
NewMsgNotArrow.Controls.Add(b);
}
and here is my java script function:
function DisplayMessage(messages, from, username) {
document.getElementById("AllMessages").innerText ="";
document.getElementById("DivDisplayMessage").style.visibility = "visible";
document.getElementById("lblChatwith").innerText = from;
var MessageForEachUser = messages.split("$SAMECHATNEWTEXT$");
for (var i = 0; i < MessageForEachUser.length; i++)
{
var ck = MessageForEachUser[i].indexOf("$" + from.toUpperCase() + "$") > -1;
if (ck == true) {
document.getElementById("AllMessages").innerText += from.toUpperCase() + ":\n";
var temp = MessageForEachUser[i].split("$" + from.toUpperCase() + "$");
MessageForEachUser[i] = temp[0];
}
if (ck == false) {
document.getElementById("AllMessages").innerText += username.toUpperCase() + ":\n";
var temp = MessageForEachUser[i].split("$" + username.toUpperCase() + "$");
MessageForEachUser[i] = temp[0];
}
document.getElementById("AllMessages").innerText += MessageForEachUser[i] + "\n______________________________________________________" + "\n";
}
return false;
}
every thing is working well but, when i want to use one of the labels like "lblchatwith" from code behind it return an empty string.

Javascript function - works in IE, not in chrome

To preface this, we are a small organization and this system was built by someone long ago. I am a total novice at javascript so I have trouble doing complicated things, but I will do my best to understand your answers. But unfortunately redoing everything from scratch is not really an option at this point.
We have a system of collecting data where clients use a login to verify a member ID, which the system then uses to pull records from an MS Access database to .ASP/html forms so clients can update their data. One of these pages has the following function that runs on form submit to check that data in fields a/b/c sum to the same total as d/e/f/g/h/i. It does this separately for each column displayed (each column is a record in the database, each a/b/c/d/e/f is a field in the record.)
The problem is with this section of the function:
for (var j=0; j<recCnt; j++) {
sumByType = milesSurf[j] + milesElev[j] + milesUnder[j];
sumByTrack = milesSingle[j] + milesDouble[j] + milesTriple[j] + milesQuad[j] + milesPent[j] + milesSex[j];
etc.
It should use javascript FOR to loop through each record and test to see if they sum to the same thing.
In Firefox and IE this is working properly; the fields sum properly into "sumByType" and "sumByTrack". You can see below I added a little alert to figure out what was going wrong:
alert(sumByType + " " + j + " " + recCnt + " " + milesSurf[j] + " " + milesElev[j] + " " + milesUnder[j]);
In Chrome, that alert tells me that the components of "sumByType" and "sumByTrack" (the various "milesXXXXX" variables) are undefined.
My question is: Why in Chrome is this not working properly, when in IE and FFox it is? Any ideas?
Full function code below:
function submitCheck(formy, recCnt) {
//2/10/03: added milesQuad
//---------------checks Q#4 that Line Mileage by type is the same as by track
var milesElev = new Array();
var milesSurf = new Array();
var milesUnder = new Array();
var milesSingle = new Array();
var milesDouble = new Array();
var milesTriple = new Array();
var milesQuad = new Array();
var milesPent = new Array();
var milesSex = new Array();
var sumByType = 0;
var milesLineTrack = new Array(); //this is for Q5 to compare it to mileage by trackage
var j = 0; var sumByTrack = 0; var liney; var yrOp;
//var str = "document.frm.milesElev" + j;
//alert(str.value);
for (var i in document.frm) {
if (i.substring(0, i.length - 1) == "milesElev") {
milesElev[parseInt(i.substring(i.length-1, i.length))] = parseFloat(document.frm[i].value); }
if (i.substring(0, i.length - 1) == "milesSurf") {
milesSurf[parseInt(i.substring(i.length-1, i.length))] = parseFloat(document.frm[i].value); }
if (i.substring(0, i.length - 1) == "milesUnder") {
milesUnder[parseInt(i.substring(i.length-1, i.length))] = parseFloat(document.frm[i].value); }
if (i.substring(0, i.length - 1) == "milesSingle") {
milesSingle[parseInt(i.substring(i.length-1, i.length))] = parseFloat(document.frm[i].value); }
if (i.substring(0, i.length - 1) == "milesDouble") {
milesDouble[parseInt(i.substring(i.length-1, i.length))] = parseFloat(document.frm[i].value); }
if (i.substring(0, i.length - 1) == "milesTriple") {
milesTriple[parseInt(i.substring(i.length-1, i.length))] = parseFloat(document.frm[i].value); }
if (i.substring(0, i.length - 1) == "milesQuad") {
milesQuad[parseInt(i.substring(i.length-1, i.length))] = parseFloat(document.frm[i].value); }
if (i.substring(0, i.length - 1) == "milesPent") {
milesPent[parseInt(i.substring(i.length-1, i.length))] = parseFloat(document.frm[i].value); }
if (i.substring(0, i.length - 1) == "milesSex") {
milesSex[parseInt(i.substring(i.length-1, i.length))] = parseFloat(document.frm[i].value); }
if (i.substring(0, i.length -1) == "milesLineTrack") {
milesLineTrack[parseInt(i.substring(i.length-1, i.length))] = document.frm[i].value; } //12/13/02 used to be parseFloat(document.frm[i].value)
if (i.substring(0,5)=="Lines") {
liney = document.frm[i].value;
if (parseInt(liney)<1 || isNaN(liney)) {
alert("Each mode must have at least 1 line. Please correct the value in question #2.");
document.frm[i].select(); return false; }}
if (i.substring(0,8)=="yearOpen") {
yrOp = document.frm[i].value;
if (parseInt(yrOp)<1825 || isNaN(yrOp)) {
alert("Please enter a year after 1825 for question #3");
document.frm[i].select(); return false; }
}
}
for (var j=0; j<recCnt; j++) {
sumByType = milesSurf[j] + milesElev[j] + milesUnder[j];
sumByTrack = milesSingle[j] + milesDouble[j] + milesTriple[j] + milesQuad[j] + milesPent[j] + milesSex[j];
//---------------to round sumByTrack and sumByType from a long decimal to a single decimal place, like frm 7.89999998 to 7.9.
sumByTrack = sumByTrack * 10;
if (sumByTrack != parseInt(sumByTrack)) {
if (sumByTrack - parseInt(sumByTrack) >= .5) {
//round up
sumByTrack = parseInt(sumByTrack) + 1; }
else { //truncate
sumByTrack = parseInt(sumByTrack); }}
sumByTrack = sumByTrack / 10;
sumByType = sumByType * 10;
if (sumByType != parseInt(sumByType)) {
if (sumByType - parseInt(sumByType) >= .5) {
//round up
sumByType = parseInt(sumByType) + 1; }
else { //truncate
sumByType = parseInt(sumByType); }}
sumByType = sumByType / 10;
//-------------end of rounding ---------------------------
if (sumByType != sumByTrack) {
if (isNaN(sumByType)) {
sumByType = "(sum of 4.a., b., and c.) "; }
else {
sumByType = "of " + sumByType; }
if (isNaN(sumByTrack)) {
sumByTrack = "(sum of 4.d., e., f., g., h., and i.) "; }
else {
sumByTrack = "of " + sumByTrack; }
alert("For #4, the 'End-to-End Mileage By Type' " + sumByType + " must equal the 'End-to-end Mileage By Trackage' " + sumByTrack + ".");
alert(sumByType + " " + j + " " + recCnt + " " + milesSurf[j] + " " + milesElev[j] + " " + milesUnder[j]);
return false;
}
//alert (milesLineTrack[j] + " " + milesSingle[j] + " " + 2*milesDouble[j] + " " + 3*milesTriple[j] + " " + 4*milesQuad[j] + " " + 5*milesPent[j] + " " + 6*milesSex[j]);
var singDoubTrip = (milesSingle[j] + 2*milesDouble[j] + 3*milesTriple[j] + 4*milesQuad[j] + 5*milesPent[j] + 6*milesSex[j])
//----------round singDoubTrip to one digit after the decimal point (like from 6.000000001 to 6.0)
singDoubTrip = singDoubTrip * 10;
if (singDoubTrip != parseInt(singDoubTrip)) {
if (singDoubTrip - parseInt(singDoubTrip) >= .5) {
//round up
singDoubTrip = parseInt(singDoubTrip) + 1; }
else { //truncate
singDoubTrip = parseInt(singDoubTrip); }}
singDoubTrip = singDoubTrip / 10;
//----------end round singDoubTrip-----------------------------------------
if (parseFloat(milesLineTrack[j]) != singDoubTrip) {
//var mlt = milesLineTrack[j];
//if isNaN(milesLineTrack[j]) { mlt =
alert("For column #" + (j+1) + ", the mainline passenger track mileage of " + milesLineTrack[j] + " must equal the single track plus 2 times the double track plus 3 times the triple track plus 4 times the quadruple track plus 5 times the quintuple track plus 6 times the sextuple track, which is " + singDoubTrip + ".");
return false;
}
}
//---------------------end of checking Q#4----------------
//return false;
}

I think for (var i in document.frm) is the problem. You should not enumerate a form element, there will be plenty of unexpected properties - see Why is using "for...in" with array iteration a bad idea?, which is especially true for array-like objects. I can't believe this works properly in FF :-)
Use this:
var ele = document.frm.elements; // or even better document.getElementById("frm")
for (var i=0; i<ele.length; i++) {
// use ele[i] to access the element,
// and ele[i].name instead of i where you need the name
}
Also, you should favour a loop over those gazillion of if-statements.