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Unable to Delete Cells using JavaScript: The value provided (3) is outside the range

function selectTo(cell) {
var row = cell.parent();
var cellIndex = cell.index();
var rowIndex = row.index();
var rowStart, rowEnd, cellStart, cellEnd;
if (rowIndex < startRowIndex) {
rowStart = rowIndex;
rowEnd = startRowIndex;
sessionStorage.setItem('rowStart', rowStart);
sessionStorage.setItem('rowEnd', rowEnd);
} else {
rowStart = startRowIndex;
rowEnd = rowIndex;
sessionStorage.setItem('rowStart', rowStart);
sessionStorage.setItem('rowEnd', rowEnd);
}
if (cellIndex < startCellIndex) {
cellStart = cellIndex;
cellEnd = startCellIndex;
sessionStorage.setItem('cellStart', cellStart);
sessionStorage.setItem('cellEnd', cellEnd);
} else {
cellStart = startCellIndex;
cellEnd = cellIndex;
sessionStorage.setItem('cellStart', cellStart);
sessionStorage.setItem('cellEnd', cellEnd);
}
for (var i = rowStart; i <= rowEnd; i++) {
var TableID = sessionStorage.getItem("TableID");
var table6 = document.getElementById(TableID);
var row6 = table6.getElementsByTagName('tr')[i];
var rowCells = row6.getElementsByTagName('td');
for (var j = cellStart; j <= cellEnd; j++) {
rowCells[j].className = "hover";
}
}
}
var TableID = sessionStorage.getItem("TableID");
var cellStart = sessionStorage.getItem("cellStart");
var cellEnd = sessionStorage.getItem("cellEnd");
var rowStart = sessionStorage.getItem("rowStart");
var rowEnd = sessionStorage.getItem("rowEnd");
for (var i = rowStart; i <= rowEnd; i++) {
var myTable = document.getElementById(TableID);
var row10 = myTable.getElementsByTagName('tr')[i];
var rowCells = row10.getElementsByTagName('td');
for (var j = cellStart; j < cellEnd; j++) {
if (j === cellStart && i === rowStart)
continue;
//rowCells[j].style.display = "none";
myTable.rows[i].deleteCell(j);
}
}
When I delete cells, use a different method table.row[i].deleteCell(j); or removechild I get out of range error.
mesage:
Uncaught DOMException: Failed to execute 'deleteCell' on
'HTMLTableRowElement': The value provided (3) is outside the range [0,
3).
at init.callback

I find solution:
var listHover = document.querySelectorAll('.hover');
for (var i = 0; i < listHover.length; i++) {
if (i > 0) {
listHover[i].style.display = 'none';
}
}

Reload popup with information

I have a table in my popup and I save the values entered by a user to localStorage. Here are the snippets.
popup.html
<table id="main_table">
</table>
<script src="popup.js"></script>
popup.js
function create_row() {
localStorage["last_session"] = true;
var table = document.getElementById("main_table");
var n = table.rows.length;
var m = table.rows[0].cells.length;
var row = table.insertRow(n);
if (!localStorage['use_storage']) {
if (n === 1) {
localStorage["cells"] = JSON.stringify([{}]);
}
else if (n > 1) {
var cells = JSON.parse(localStorage["cells"]);
cells.push({});
localStorage["cells"] = JSON.stringify(cells);
}
}
var cell = row.insertCell(0);
cell.innerHTML = n;
for (j=1; j<m; j++) {
create_cell(n-1, j, row);
}
return row
}
function create_cell(i, j, row){
var cell = row.insertCell(j);
if (j == 1) {
cell.innerHTML = "<input size=10>";
}
else {
cell.innerHTML = "<input size=4>";
}
cell.addEventListener("change", function () {
var cells = JSON.parse(localStorage["cells"]);
cells[i.toString()][j.toString()] = cell.childNodes[0].value;
localStorage["cells"] = JSON.stringify(cells);
})
}
document.getElementById('create_row').onclick = create_row;
// restore a table
if (localStorage["last_session"]) {
localStorage["use_storage"] = true;
try {
var cells = JSON.parse(localStorage["cells"]);
var n = cells.length;
var table = document.getElementById("main_table")
for (i=0; i<n; i++) {
var row = create_row(true);
var cell = cells[i]
for (var key in cell) {
if (cell.hasOwnProperty(key)) {
var col = parseInt(key);
var val = cell[key];
row.cells[col].childNodes[0].value = val;
}
}
}
} catch (e) {
console.log("Catched error");
console.log(e);
}
if (localStorage["results"]) {
show_results();
}
localStorage['use_storage'] = false;
}
In my browser it works as it is supposed, that is after refreshing a page popup.html I have the state where I left (number of rows and values are preserved). However, in my chrome extension, after clicking to any area and thus reloading the extension, I have the initial empty table.
How can I preserve the table in this particular case?

Javascript calculator backspace not working on first time

I am in the process of creating a calculator in javascript, and am trying to make a backspace. My initial thought was to use the .slice function, and it works, to a point. It works in the way that it takes a number off, but I am having trouble getting it to actually take off the number from the first value, if that makes any sense. It doesn't work on the first time, for example, if I type in 12, then use the backspace, then make the number 13 and do 13 + 6; it will come up with NaN. However if I do that same process again, it works as long as i use my clear button and not refresh the page. I have tried everything I can think of, bu't can't get it to work. Here is the code, sorry its a lot, but I figured it be better to have it all there. I am open to any suggestions, but prefer not to use jQuery, as I haven't yet learned a single thing about jQuery
Code:
//Variables
var xValue = 0;
var xValue2 = 0;
//Button Values
var plusButton = 0;
var subButton = 0;
var timesButton = 0;
var divideButton = 0;
var squaredButton = 0;
var powerButton = 0;
//Answers
var sum = 0;
var difference = 0;
var product = 0;
var quotent = 0;
var square = 0;
var power = 0;
//Functions
function add () {
if (plusButton >= 1) {
xValue2 = xValue;
xValue = "";
}
subButton = 0;
timesButton = 0;
divideButton = 0;
squaredButton = 0;
powerButton = 0;
//alert(xValue);
}
function addFunction () {
sum = +xValue + +xValue2;
answer.innerHTML = sum;
}
function subtract () {
if (subButton >= 1) {
xValue2 = xValue;
xValue = "";
}
plusButton = 0;
timesButton = 0;
divideButton = 0;
squaredButton = 0;
powerButton = 0;
}
function subtractFunction () {
difference = +xValue2 - +xValue1;
answer.innerHTML = difference;
}
function multiply () {
if(timesButton >= 1) {
temp = xValue2;
xValue2 = xValue;
xValue = "";
}
subButton = 0;
plusButton = 0;
divideButton = 0;
squaredButton = 0;
powerButton = 0;
}
function multiplyFunction () {
product = +xValue * +xValue2;
answer.innerHTML = product;
}
function divide () {
if(divideButton >= 1) {
temp = xValue2;
xValue2 = xValue;
xValue = "";
}
subButton = 0;
plusButton = 0;
timesButton = 0;
squaredButton = 0;
powerButton = 0;
}
function divideFunction () {
var quotent = +xValue / +xValue2;
answer.innerHTML = quotent;
}
function squared () {
subButton = 0;
plusButton = 0;
timesButton = 0;
divideButton = 0;
powerButton = 0;
}
function squaredFunction () {
square = Math.pow(xValue, 2);
answer.innerHTML = square;
}
function powerNum () {
if(powerButton >= 1) {
xValue2 = xValue;
xValue = "";
}
plusButton = 0;
subButton = 0;
timesButton = 0;
divideButton = 0;
squaredButton = 0;
}
function powerFunction () {
var power = Math.pow(xValue2, xValue);
answer.innerHTML = power;
}
function compute () {
if(plusButton >= 1) {
addFunction();
xValue = sum;
}
else if (subButton >= 1) {
subtractFunction();
xValue = difference;
}
else if (timesButton >= 1) {
multiplyFunction();
xValue = product;
}
else if (divideButton >= 1) {
divideFunction();
xValue = quotent;
}
else if (squaredButton >= 1) {
squaredFunction();
xValue = square;
}
else if (powerButton >= 1) {
powerFunction();
xValue2 = power;
}
xValue2 = 0;
plusButton = 0;
subButton = 0;
timesButton = 0;
divideButton = 0;
squaredButton = 0;
powerButton = 0;
}
function clearScreen() {
answer.innerHTML = "";
xValue = 0;
plusButton = 0;
xValue2 = 0;
temp = 0;
}
function backOne () {
var str = answer.innerHTML;
var res = str.slice(0, -1);
answer.innerHTML = res;
xValue = parseInt(res);
}

You can use substring on the current displayed value in the calculator and replace the current value with the substring of it. The substring would be (0, length - 1).
http://www.w3schools.com/jsref/jsref_substring.asp
EDIT: should be length - 1

Why does my string permutation algorithm only work with 3 or less letters?

The Code:
function recursiveParse(letters, index) {
var i,
index = index || 0;
stringOfLetters = '';
while(index < letters.length) {
stringOfLetters += letters[index] + recursiveParse(letters, ++index);
}
return stringOfLetters;
}
function calcPermutations(letters, index, permutations) {
var head,
index = index || 0,
i,
swapLetters,
permutation,
permutations = permutations || {};
swapLetters = function(letters, index1, index2) {
var tmp = letters[index2];
letters[index2] = letters[index1];
letters[index1] = tmp;
return letters;
}
if(index < letters.length) {
head = letters.splice(index, 1).join('');
for(i = 0; i < letters.length; i++) {
permutation = head + swapLetters(letters.slice(0), index, i).join('');
permutations[permutation] = true;
}
letters.splice(index, 0, head);
calcPermutations(letters, ++index, permutations);
}
return permutations;
}
function testPermutations() {
var expectedPermutations = ['atr', 'rat', 'rta', 'tar', 'tra', 'art'],
actualPermutations = calcPermutations(['a', 'r', 't']);
for(var i = 0; i < expectedPermutations.length - 1; i++) {
if(actualPermutations[expectedPermutations[i]] !== true) {
console.log("You're missing " + expectedPermutations[i]);
} else {
console.log("You've got " + expectedPermutations[i]);
}
}
return actualPermutations;
}
testPermutations();
When I run testPermutations and pass in a 3 letter word, it works fine. However, when I try four, a bunch of permutations are coming up missing. What's the flaw in my logic?

Mccluskey algorithm, javascript

<html>
<body>
<script type="text/javascript">
start();
function start() {
var val = "0,1";
var n = 5;
var chars = ['a', 'b', 'c', 'd', 'e'];
gVars = chars.slice(0, n);
for (var i = 0; i < gVars.length; i++)
document.write(gVars[i] + "<br />");
var termsStr = val.split(',');
for (var i = 0; i < termsStr.length; i++)
document.write(termsStr[i] + "<br />");
var gOrigTerms = [];
var maxterm = Math.pow(2, termsStr.length) - 1;
document.write("maxterm: " + maxterm + "<br />");
for (var i = 0; i < termsStr.length; i++) {
gOrigTerms[i] = parseInt(termsStr[i]);
document.write(gOrigTerms[i] + "<br />");
if (gOrigTerms[i] > maxterm) document.write("Invalid term in term list." + "<br />");
}
gFormula = new Formula(gVars, gOrigTerms);
document.write(gFormula);
gFormula.toString();
gFormula.reduceToPrimeImplicants(); //here the breakpoint is inserted
}
function Formula(vars, terms)
{
this.vars = vars;
this.termList = [];
for (var i = 0; i < terms.length; i++) {
this.termList[i] = new Term(Dec2Bin(terms[i], vars.length));
document.write("this.termList" + this.termList[i] + "<br />");
}
this.orginalTermList = [];
document.write("this.orginalTermList" + this.orginalTermList + "<br />");
}
function Dec2Bin(dec, size) {
var bits = [];
for (var bit = 0; bit < size; bit++)
{
bits[bit] = 0;
}
var i = 0;
while (dec > 0)
{
if (dec % 2 == 0)
{
bits[i] = 0;
} else
{
bits[i] = 1;
}
i++;
dec = (dec / 2) | 0;
// Or with zero casts result to int (who knows why...)
}
bits.reverse();
return bits;
}
function Term(varVals)
{
this.varVals = varVals;
document.write("this.varVals: " + this.varVals);
}
function reduceToPrimeImplicants() //there is some problem with this function
{
this.originalTermList = this.termList.slice(0);
var numVars = this.termList[0].getNumVars();
var table = [];
for (var dontKnows = 0; dontKnows <= numVars; dontKnows++) {
table[dontKnows] = [];
for (var ones = 0; ones <= numVars; ones++) {
table[dontKnows][ones] = [];
}
table[dontKnows][numVars + 1] = [];
}
table[numVars + 1] = [];
table[numVars + 1][numVars + 1] = [];
for (var i = 0; i < this.termList.length; i++) {
var dontCares = this.termList[i].countValues(DontCare);
var ones = this.termList[i].countValues(1);
var len = table[dontCares][ones].length;
table[dontCares][ones][len] = this.termList[i];
}
for (var dontKnows = 0; dontKnows <= numVars - 1; dontKnows++) {
for (var ones = 0; ones <= numVars - 1; ones++) {
var left = table[dontKnows][ones];
var right = table[dontKnows][ones + 1];
var out = table[dontKnows + 1][ones];
for (var leftIdx = 0; leftIdx < left.length; leftIdx++) {
for (var rightIdx = 0; rightIdx < right.length; rightIdx++) {
var combined = left[leftIdx].combine(right[rightIdx]);
if (combined != null) {
if (out.indexOf(combined) < 0) {
var len = out.length;
out[len] = combined;
}
if (this.termList.indexOf(left[leftIdx]) >= 0) {
this.termList.splice(this.termList.indexOf(left[leftIdx]), 1);
}
if (this.termList.indexOf(right[rightIdx]) >= 0) {
this.termList.splice(this.termList.indexOf(right[rightIdx]), 1);
}
if (this.termList.indexOf(combined) < 0) {
var len = this.termList.length;
this.termList[len] = combined;
}
}
}
}
}
}
}
function getNumVars()
{
return this.varVals.length;
}
function countValues(value)
{
result = 0;
for (var i = 0; i < this.varVals.length; i++) {
if (this.varVals[i] == value) {
result++;
}
}
return result;
}
function combine(term)
{
var diffVarNum = -1; // The position where they differ
for (var i = 0; i < this.varVals.length; i++) {
{
if (this.varVals[i] != term.varVals[i])
if (diffVarNum == -1) {
diffVarNum = i;
} else { // They're different in at least two places return null; }
}
}
if (diffVarNum == -1)
{
// They're identical return null;
}
resultVars = this.varVals.slice(0);
resultVars[diffVarNum] = DontCare;
return new Term(resultVars);
}
</script>
</body>
</html>
In the above code, that is not complete, but which implements quine Mccluskey algorithm. There is a problem while it is debugged.
If a breakpoint is inserted at gFormula.reducetoPrimeImplicants(); the debugger does not go into that function. This is the last function called in the code until now. But, it does go to start(), which is the first function.
There is some problem in reducetoPrimeImplicants(); function because it also gives ERROR in internet explorer.
I am not able to figure out the error. If I remove reducetoPrimeImplicants(); function from the code the works fine.
Please, can somebody tell me why the debugger does not enter reducetoPrimeImplicants();.
I am using the Firebug debugger.
Thanks in advance.

The last function in your page combine() is missing a closing brace.
If you don't mind, a suggestion: Please use http://jsbeautifier.org/ or some similar tool to indent your code better.

Your For loop has two starting braces.
for (var i = 0; i < this.varVals.length; i++) {
{
So remove one. This should solve your problem.