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Passing hands of cards around a table in Javascript

This seems like a stupidly simple thing to do, but I can't figure out what I'm doing wrong. The goal is to have an array of 8 other arrays, which each contain hands of cards (in the example, the arrays just contain arbitrary numbers). Then, depending on whether passDirection is set to -1 or 1, each array is cycled through and replaced with the one next to it. The desired end result is that the values of playerList essentially shift by 1 either up or down, and this can be repeated several times without issue.
What's actually happening with the code I have below, though, is that all the arrays are just being replaced with what's at index 0, except for the first one. How can I fix this?
var playerList = new Array;
var passDirection = -1;
for(i = 0; i < 8; i++) {
playerList.push([playerList.length,i]); // Fill Arrays with arbitrary data
}
for (i=0; i< playerList.length; i++) {
console.log(i + ": " + playerList[i]); // Check their values before anything is done to them
}
for(q=0; q < 5; q++){ // Repeat the process 5 times, just because.
var bufferArray = playerList[0]; // Put Array Element 0's value in a buffer as it will be replaced first
for(i = 0; i < playerList.length && i > (playerList.length * -1); i += passDirection) {
var catcher = i; // 'catcher' should be the array that gets replaced
var passer = catcher - passDirection; // 'passer' should be the one it gets replaced with
if (catcher < 0) {
catcher = catcher + playerList.length;
}
if (passer < 0) {
passer = passer + playerList.length;
} else if (passer >= playerList.length) {
passer = passer - playerList.length;
}
if (passer == 0) {
playerList[catcher] = bufferArray;
} else {
playerList[catcher] = playerList[passer];
}
}
for (i=0; i< playerList.length; i++) {
console.log(i + ": " + playerList[i]);
}
console.log("...");
}
https://jsfiddle.net/3r1Lhwc5

You have two errors in your code:
if (passer = 0) is performing an assignment. You need if (passer === 0).
The passer index is looking at the wrong side of the value. Currently you are first getting from 1 and putting at 0, then getting from 0 and putting at 7 (i.e. -1). Notice how you are moving the same value in the second iteration. You need to change passer = catcher - passDirection to passer = catcher + passDirection
Note that all this can be done much easier with the splice, shift, unshift, pop and push Array methods (on the main playerList).

You can make your life easier by using Array methods to move elements from the beginning to end of an array or vice versa. Using this in the body of your for loop should do the trick:
if (passDirection === -1) {
const first = playerList.shift();
playerList.push(first);
}
else {
const last = playerList.pop();
playerList.unshift(last);
}

Pull information from a data file?

I have over 170000 entries of data in data file in this format:
1479661:-1,1,-1,-898,-769,0.00;-1,2,-1,-96,-1402,0.00;-1,3,-1,117,-1397,0.00;-1,4,-1,-4,-2420,0.00;4,5,-1,5570,4395,0.00;4,6,-1,5570,4395,0.00;4,7,-1,5570,4395,0.00;4,8,-1,5570,4395,0.00;4,9,-1,5570,4395,0.00;4,10,-1,5570,4395,0.00;4,11,-1,5570,4395,0.00;4,12,-1,5570,4395,0.00;4,13,-1,5570,4395,0.00;4,14,-1,5570,4395,0.00;-1,15,-1,913,-3533,0.00;4,16,-1,5570,4395,0.00;4,17,-1,5570,4395,0.00;4,18,-1,5570,4395,0.00;4,19,-1,5570,4395,0.00;4,20,-1,5570,4395,0.00;4,21,-1,5570,4395,0.00;4,22,-1,5570,4395,0.00;4,23,-1,5570,4395,0.00;4,24,-1,5570,4395,0.00;4,25,-1,5570,4395,0.00;4,26,-1,5570,4395,0.00;4,27,-1,5570,4395,0.00;4,28,-1,5570,4395,0.00;4,29,-1,5570,4395,0.00;:117,-1397,7,7.00,A,Dead;:
1479662:-1,1,-1,-898,-769,0.00;-1,2,-1,-96,-1402,0.00;-1,3,-1,117,-1392,0.00;-1,4,-1,-6,-2419,0.00;4,5,-1,5570,4395,0.00;4,6,-1,5570,4395,0.00;4,7,-1,5570,4395,0.00;4,8,-1,5570,4395,0.00;4,9,-1,5570,4395,0.00;4,10,-1,5570,4395,0.00;4,11,-1,5570,4395,0.00;4,12,-1,5570,4395,0.00;4,13,-1,5570,4395,0.00;4,14,-1,5570,4395,0.00;-1,15,-1,913,-3533,0.00;4,16,-1,5570,4395,0.00;4,17,-1,5570,4395,0.00;4,18,-1,5570,4395,0.00;4,19,-1,5570,4395,0.00;4,20,-1,5570,4395,0.00;4,21,-1,5570,4395,0.00;4,22,-1,5570,4395,0.00;4,23,-1,5570,4395,0.00;4,24,-1,5570,4395,0.00;4,25,-1,5570,4395,0.00;4,26,-1,5570,4395,0.00;4,27,-1,5570,4395,0.00;4,28,-1,5570,4395,0.00;4,29,-1,5570,4395,0.00;:117,-1392,7,7.07,A,Dead;:
Now each data array starts with a unique id and i was wondering is there a convenient way to push each entry 1479661 then 1479662 every second to an array and assign the values within the unique id into 6 fields that update.
Now I ask if there is a more convenient way as currently I am using this method:
Data comprises of three chunks in a single line
Split the link into chunks
var chunkOne = [1479661];
var chunkTwo = [-1,1,-1,-898,-769,0.00,-1,2,-1,-96,-1402,0.00,-1,3,-1,117,-1397,0.00,-1,4,-1,-4,-2420,0.00,4,5,-1,5570,4395,0.00,4,6,-1,5570,4395,0.00,4,7,-1,5570,4395,0.00,4,8,-1,5570,4395,0.00,4,9,-1,5570,4395,0.00,4,10,-1,5570,4395,0.00,4,11,-1,5570,4395,0.00,4,12,-1,5570,4395,0.00,4,13,-1,5570,4395,0.00,4,14,-1,5570,4395,0.00,-1,15,-1,913,-3533,0.00,4,16,-1,5570,4395,0.00,4,17,-1,5570,4395,0.00,4,18,-1,5570,4395,0.00,4,19,-1,5570,4395,0.00,4,20,-1,5570,4395,0.00,4,21,-1,5570,4395,0.00,4,22,-1,5570,4395,0.00,4,23,-1,5570,4395,0.00,4,24,-1,5570,4395,0.00,4,25,-1,5570,4395,0.00,4,26,-1,5570,4395,0.00,4,27,-1,5570,4395,0.00,4,28,-1,5570,4395,0.00,4,29,-1,5570,4395,0.00];
var chunkThree = [117,-1397,7,7.00,"A","Dead"];
Then get length of each array:
var chunkOneLength = chunkOne.length;
var chunkTwoLength = chunkTwo.length;
var chunkThreeLength = chunkThree.length;
Pick out the nth value in the array depending on the data chunk:
//uniqueID set as first
for (var i = 0; i < chunkOneLength; i = i + 1) {
// useful code would go here
alert("This is the unique ID " + chunkOne[i]);
}
//teamval
for (var i = 0; i < chunkTwoLength; i = i + 6) {
// useful code would go here
alert("This is the teamVal " + chunkTwo[i]);
}
Now the only problem I see with this method, is that the original data array will need to be formatted and separated into chunks every time.

As you have a separator on each section i.e. : you can actually use split to split them up like below and push them into a array and only have to do 2 loops - firstly pushing the split data in a new array and then looping through them and populating the structure.
Please note as long as each chunk of data is separated with : this will work with anything even if you expand the data later. obviously it will not work if you remove the : separator.
example below:
var splitChucks = [];
var chucks = [ "1479661:-1,1,-1,-898,-769,0.00;-1,2,-1,-96,-1402,0.00;-1,3,-1,117,-1397,0.00;-1,4,-1,-4,-2420,0.00;4,5,-1,5570,4395,0.00;4,6,-1,5570,4395,0.00;4,7,-1,5570,4395,0.00;4,8,-1,5570,4395,0.00;4,9,-1,5570,4395,0.00;4,10,-1,5570,4395,0.00;4,11,-1,5570,4395,0.00;4,12,-1,5570,4395,0.00;4,13,-1,5570,4395,0.00;4,14,-1,5570,4395,0.00;-1,15,-1,913,-3533,0.00;4,16,-1,5570,4395,0.00;4,17,-1,5570,4395,0.00;4,18,-1,5570,4395,0.00;4,19,-1,5570,4395,0.00;4,20,-1,5570,4395,0.00;4,21,-1,5570,4395,0.00;4,22,-1,5570,4395,0.00;4,23,-1,5570,4395,0.00;4,24,-1,5570,4395,0.00;4,25,-1,5570,4395,0.00;4,26,-1,5570,4395,0.00;4,27,-1,5570,4395,0.00;4,28,-1,5570,4395,0.00;4,29,-1,5570,4395,0.00;:117,-1397,7,7.00,A,Dead;:", "1479662:-1,1,-1,-898,-769,0.00;-1,2,-1,-96,-1402,0.00;-1,3,-1,117,-1392,0.00;-1,4,-1,-6,-2419,0.00;4,5,-1,5570,4395,0.00;4,6,-1,5570,4395,0.00;4,7,-1,5570,4395,0.00;4,8,-1,5570,4395,0.00;4,9,-1,5570,4395,0.00;4,10,-1,5570,4395,0.00;4,11,-1,5570,4395,0.00;4,12,-1,5570,4395,0.00;4,13,-1,5570,4395,0.00;4,14,-1,5570,4395,0.00;-1,15,-1,913,-3533,0.00;4,16,-1,5570,4395,0.00;4,17,-1,5570,4395,0.00;4,18,-1,5570,4395,0.00;4,19,-1,5570,4395,0.00;4,20,-1,5570,4395,0.00;4,21,-1,5570,4395,0.00;4,22,-1,5570,4395,0.00;4,23,-1,5570,4395,0.00;4,24,-1,5570,4395,0.00;4,25,-1,5570,4395,0.00;4,26,-1,5570,4395,0.00;4,27,-1,5570,4395,0.00;4,28,-1,5570,4395,0.00;4,29,-1,5570,4395,0.00;:117,-1392,7,7.07,A,Dead;:"];
for (var i = 0; i < chucks.length; i++){
splitChucks.push(chucks[i].split(':'))
}
for (var h = 0; h < splitChucks.length; h++) {
alert("This is the unique ID " + splitChucks[h][0]);
alert("This is the teamVal " + splitChucks[h][1]);
}
Hope this helps, this is a much more efficient way to do your task :)

var splitChucks = [];
var chucks = [ "1479661:-1,1,-1,-898,-769,0.00;-1,2,-1,-96,-1402,0.00;-1,3,-1,117,-1397,0.00;-1,4,-1,-4,-2420,0.00;4,5,-1,5570,4395,0.00;4,6,-1,5570,4395,0.00;4,7,-1,5570,4395,0.00;4,8,-1,5570,4395,0.00;4,9,-1,5570,4395,0.00;4,10,-1,5570,4395,0.00;4,11,-1,5570,4395,0.00;4,12,-1,5570,4395,0.00;4,13,-1,5570,4395,0.00;4,14,-1,5570,4395,0.00;-1,15,-1,913,-3533,0.00;4,16,-1,5570,4395,0.00;4,17,-1,5570,4395,0.00;4,18,-1,5570,4395,0.00;4,19,-1,5570,4395,0.00;4,20,-1,5570,4395,0.00;4,21,-1,5570,4395,0.00;4,22,-1,5570,4395,0.00;4,23,-1,5570,4395,0.00;4,24,-1,5570,4395,0.00;4,25,-1,5570,4395,0.00;4,26,-1,5570,4395,0.00;4,27,-1,5570,4395,0.00;4,28,-1,5570,4395,0.00;4,29,-1,5570,4395,0.00;:117,-1397,7,7.00,A,Dead;:", "1479662:-1,1,-1,-898,-769,0.00;-1,2,-1,-96,-1402,0.00;-1,3,-1,117,-1392,0.00;-1,4,-1,-6,-2419,0.00;4,5,-1,5570,4395,0.00;4,6,-1,5570,4395,0.00;4,7,-1,5570,4395,0.00;4,8,-1,5570,4395,0.00;4,9,-1,5570,4395,0.00;4,10,-1,5570,4395,0.00;4,11,-1,5570,4395,0.00;4,12,-1,5570,4395,0.00;4,13,-1,5570,4395,0.00;4,14,-1,5570,4395,0.00;-1,15,-1,913,-3533,0.00;4,16,-1,5570,4395,0.00;4,17,-1,5570,4395,0.00;4,18,-1,5570,4395,0.00;4,19,-1,5570,4395,0.00;4,20,-1,5570,4395,0.00;4,21,-1,5570,4395,0.00;4,22,-1,5570,4395,0.00;4,23,-1,5570,4395,0.00;4,24,-1,5570,4395,0.00;4,25,-1,5570,4395,0.00;4,26,-1,5570,4395,0.00;4,27,-1,5570,4395,0.00;4,28,-1,5570,4395,0.00;4,29,-1,5570,4395,0.00;:117,-1392,7,7.07,A,Dead;:"];
for (var i = 0; i < chucks.length; i++){
splitChucks.push(chucks[i].split(':'))
}
for (var h = 0; h < splitChucks.length; h++) {
alert("This is the unique ID " + splitChucks[h][0]);
alert("This is the teamVal " + splitChucks[h][1]);
}

One of the best purposes of an unique ID is to act as an index. So, instead of iterating over your index array (chunkOne), use ID as an Object key!
// 1479661:-1,1,-1,-898,-769,0.00;-1,2,-1,-96,-1402,0.00;-1,3,-1,117,-1397,0.00;-1,4,-1,-4,-2420,0.00;4,5,-1,5570,4395,0.00;4,6,-1,5570,4395,0.00;4,7,-1,5570,4395,0.00;4,8,-1,5570,4395,0.00;4,9,-1,5570,4395,0.00;4,10,-1,5570,4395,0.00;4,11,-1,5570,4395,0.00;4,12,-1,5570,4395,0.00;4,13,-1,5570,4395,0.00;4,14,-1,5570,4395,0.00;-1,15,-1,913,-3533,0.00;4,16,-1,5570,4395,0.00;4,17,-1,5570,4395,0.00;4,18,-1,5570,4395,0.00;4,19,-1,5570,4395,0.00;4,20,-1,5570,4395,0.00;4,21,-1,5570,4395,0.00;4,22,-1,5570,4395,0.00;4,23,-1,5570,4395,0.00;4,24,-1,5570,4395,0.00;4,25,-1,5570,4395,0.00;4,26,-1,5570,4395,0.00;4,27,-1,5570,4395,0.00;4,28,-1,5570,4395,0.00;4,29,-1,5570,4395,0.00;:117,-1397,7,7.00,A,Dead;:
var data =
{
1479661:
[
-1,1,-1,-898,-769,0.00,-1,2,-1,-96,-1402,0.00,-1,3,-1,117,-1397,0.00,-1,4,-1,-4,-2420,0.00,4,5,-1,5570,4395,0.00,4,6,-1,5570,4395,0.00,4,7,-1,5570,4395,0.00,4,8,-1,5570,4395,0.00,4,9,-1,5570,4395,0.00,4,10,-1,5570,4395,0.00,4,11,-1,5570,4395,0.00,4,12,-1,5570,4395,0.00,4,13,-1,5570,4395,0.00,4,14,-1,5570,4395,0.00,-1,15,-1,913,-3533,0.00,4,16,-1,5570,4395,0.00,4,17,-1,5570,4395,0.00,4,18,-1,5570,4395,0.00,4,19,-1,5570,4395,0.00,4,20,-1,5570,4395,0.00,4,21,-1,5570,4395,0.00,4,22,-1,5570,4395,0.00,4,23,-1,5570,4395,0.00,4,24,-1,5570,4395,0.00,4,25,-1,5570,4395,0.00,4,26,-1,5570,4395,0.00,4,27,-1,5570,4395,0.00,4,28,-1,5570,4395,0.00,4,29,-1,5570,4395,0.00,117,-1397,7,7.00,"A","Dead"
]
// More data...
};
Object.keys(data).forEach(function(key)
{
console.log('This is ID ' + key);
data[key].forEach(function(value,index,array)
{
console.log('Index ' + index + ' of data key ' + key + ':');
console.log(data[key][index]);
});
});
Test this on any modern browser's console or node.js instance to see results.

How to push into the second dimension of a two dimensional array in JavaScript?

I have a list of players in denoted as
activeRange[x]
where x will vary from day-to-day.
Each of the x values will have to have AT LEAST 4 more subsequent values (likely a bit more). Ideally I'd like the array to look like:
activeRange[x][y]
So here's what I've done so far:
var MATCH = AllData[TotalRows][TotalColumns+1];
activeRange[TotNumPlayers].push(MATCH);
This is all located within 3 nested for loops.
TotNumPlayers
will iterate through a given set declared at the beginning (somewhat like 23). Once done, the
TotalRows
will iterate, then finally
TotalColumns
I'm running into the following error:
TypeError: Cannot find function push in object mitch
mitch is the value of activeRange[0]. I've been staring at this way too long, so any help would be appreciated!
EDIT: Code inserted below:
PLEASE IGNORE ALL THE COMMENTS. I COPY/PASTED THIS FROM A BIT OF CODE I USED YESTERDAY TO PERFORM A DIFFERENT FUNCTION.
This is the second time I've ever posted on this website, so trying to format this monster to be pretty was scary sounding. Hopefully this is good enough.
This is how activeRange was declared and initialized.
var activeRange = new Array();
for (var b=0; b<=lastRow-2; b++){
activeRange[b] = sheetRANK.getRange(b+2,1).getValue();
}
This is the function.
function getTotalScore(activeRange, w) {
Logger.clear()
var ss = SpreadsheetApp.getActiveSpreadsheet();
var sheetWAR = ss.getSheetByName('WAR');
var sheetRANK = ss.getSheetByName('RANK');
var AllData = sheetRANK.getDataRange().getValues();
Logger.log('First');
for (var TotNumPlayers = 0; TotNumPlayers <= activeRange.length; TotNumPlayers++) {
Logger.log('Second');
var f = 0;
for (var TotalColumns = 0; TotalColumns <= AllData[0].length; ++TotalColumns) { // Init n. If n <= the total columns (second dimension), inc n.
Logger.log('Third');
for (var TotalRows = 0; TotalRows <= AllData.length; ++TotalRows) { // Init i. If i <= the total rows (first dimension), inc i.
Logger.log('Fourth');
//try{ // to avoid errors.
if (activeRange[TotNumPlayers] != "") {
Logger.log('Here?');
if (AllData[TotalRows][TotalColumns].valueOf().toUpperCase() == activeRange[TotNumPlayers].toUpperCase()) {
Logger.log('How About Here?');
var MATCH = AllData[TotalRows][TotalColumns + 1];
activeRange.push(TotNumPlayers, MATCH);
for (var Calc = 0; Calc <= activeRange[TotNumPlayers].length - 1; Calc++) {
var OverallScore = ((activeRange[TotNumPlayers][0] * 1.0) + (activeRange[TotNumPlayers][1] * .75) + (activeRange[TotNumPlayers][2] * .50) + (activeRange[TotNumPlayers][3] * .25));
sheetRANK.getRange(activeRange[TotNumPlayers] + 1, 2).setValue(OverallScore);
f = f + 1;
}
if (TotalRows == AllData.length - 1 && TotalColumns == AllData[0].length - 1 && f == 0) {
Browser.msgBox('No names matching \'' + activeRange[TotNumPlayers] + '\' found. Check your spelling!');
return;
}
}
}
}
}
}
}

Try thinking about what kind of data structures you can use to make your life easier. For this particular case, you have a list of players that you want to associate some data with. You'd probably use a structure like:
activeRange = [
{
name: 'mitch',
data: []
}
]
When you want to update the data, you'd simply call activeRange[0].data.push(someData).
activeRange is an array of players and each player is represented by an object with some properties, (name, data, etc).
Calling activeRange[0] yields the first player in your array and activeRange[0].data will yield the data associated with that player, which you can then manipulate however you want (push, pop, etc)

Based on your comments, you need a structure more like this
var activeRange = [
{
name: 'mitch',
otherData: [
10,
11,
12,
13
]
},
{
name: 'viper',
otherData: [
//values
]
}
]
you can access that by activeRange[0].otherData[2]
to add to it, just push into the sub array activeRange[0].otherData.push(newValue)

Finding the rank of the Given string in list of all possible permutations

I am trying to find the Rank of the given string in the list of possible permutations. I tried to come up with a solution that tries to find all possible permutations, assign a rank to them and then display it.
But this drastically reduces the performance when the length of the string keeps increasing. So was wondering if someone can think of an efficient solution for this problem..
function permute(str) {
// Sort the string
var arr = [];
for (var i = 0; i < str.length; i++) arr.push(str[i]);
var sortedString = arr.sort().join(''),
// Length of the string
length = str.length,
used = [];
// Create a boolean array for length of the string
while (length--) used.push(false);
// String buffer that holds the current string
var out = '';
// Call the function
doPermute(sortedString, str, out, used, str.length, 0);
}
var count = 0;
function doPermute(inp, givenString, out, used, length, level) {
// Only if length of the string equal to current level print it
// That is permutation length is eqaul to string length
if (level == length) {
count++;
//console.log('Perm :: ' + out + ' -- ' + count);
if (out === givenString) {
var pp = 'Rank of :: ' + out + ' -- ' + count;
$('div').append('<p>' + pp + '</p>');
}
return;
}
for (var i = 0; i < length; ++i) {
// If variable used continue
if (used[i]) continue;
// Append the current char in loop
out += inp[i];
// set variable to true
used[i] = true;
// Call the function again
doPermute(inp, givenString, out, used, length, level + 1);
// Set it to false as the variable can be reused
used[i] = false;
// remove the last character of the buffer
out = out.slice(0, out.length - 1)
}
}
permute('dbcarf')
Fiddle

Sure: if input string is "cab".
What is the lowest rank that a string starting with c could get?
c
Note the strings that come before it.
abc
acb
bac
bca
So a string starting with c has minimum rank 5.This is just number of characters in input string that come lexicographically before c.(in order a,b,c,d,e,f...)So we have 2.Each word starting with a letter can have 2 words.
Next letter is "a"?
What is minimum rank that a word starting with "ca" can get?
5
Why?
"a" is the best way we can fill the second spot with the remaining letters.
And the same goes for third element "b".
So rank of "cab" is 5.
In general.(Assuming no duplicates, though this is not much harder)
var W; //input string
var C[26];
var rank = 1;
for (var i = 0; i < W.length; i++) C[W[i] - 'a']++;
for (var i = 0; i < W.length; i++) {
//How many characters which are not used, that come before current character
var count = 0;
for (var j = 0; j < 26; j++) {
if (j == (W[i] - 'a')) break;
if (C[j] > 0) count++;
}
C[W[i] - 'a'] = 0;
rank += count * fact(W.length - i - 1);
}

There is an explanation in https://en.wikipedia.org/wiki/Permutation#Numbering_permutations of how to convert a permutation on n objects to a number in the range 0..n!-1 and it goes on to say that "Converting successive natural numbers to the factorial number system produces those sequences in lexicographic order (as is the case with any mixed radix number system), and further converting them to permutations preserves the lexicographic ordering, provided the Lehmer code interpretation is used" So I would try doing this number conversion and see if it produces something related to the rank that you need, by your definition.

Extract keyphrases from text (1-4 word ngrams)

What's the best way to extract keyphrases from a block of text? I'm writing a tool to do keyword extraction: something like this. I've found a few libraries for Python and Perl to extract n-grams, but I'm writing this in Node so I need a JavaScript solution. If there aren't any existing JavaScript libraries, could someone explain how to do this so I can just write it myself?

I like the idea, so I've implemented it: See below (descriptive comments are included).
Preview at: https://jsfiddle.net/WsKMx
/*#author Rob W, created on 16-17 September 2011, on request for Stackoverflow (http://stackoverflow.com/q/7085454/938089)
* Modified on 17 juli 2012, fixed IE bug by replacing [,] with [null]
* This script will calculate words. For the simplicity and efficiency,
* there's only one loop through a block of text.
* A 100% accuracy requires much more computing power, which is usually unnecessary
**/
var text = "A quick brown fox jumps over the lazy old bartender who said 'Hi!' as a response to the visitor who presumably assaulted the maid's brother, because he didn't pay his debts in time. In time in time does really mean in time. Too late is too early? Nonsense! 'Too late is too early' does not make any sense.";
var atLeast = 2; // Show results with at least .. occurrences
var numWords = 5; // Show statistics for one to .. words
var ignoreCase = true; // Case-sensitivity
var REallowedChars = /[^a-zA-Z'\-]+/g;
// RE pattern to select valid characters. Invalid characters are replaced with a whitespace
var i, j, k, textlen, len, s;
// Prepare key hash
var keys = [null]; //"keys[0] = null", a word boundary with length zero is empty
var results = [];
numWords++; //for human logic, we start counting at 1 instead of 0
for (i=1; i<=numWords; i++) {
keys.push({});
}
// Remove all irrelevant characters
text = text.replace(REallowedChars, " ").replace(/^\s+/,"").replace(/\s+$/,"");
// Create a hash
if (ignoreCase) text = text.toLowerCase();
text = text.split(/\s+/);
for (i=0, textlen=text.length; i<textlen; i++) {
s = text[i];
keys[1][s] = (keys[1][s] || 0) + 1;
for (j=2; j<=numWords; j++) {
if(i+j <= textlen) {
s += " " + text[i+j-1];
keys[j][s] = (keys[j][s] || 0) + 1;
} else break;
}
}
// Prepares results for advanced analysis
for (var k=1; k<=numWords; k++) {
results[k] = [];
var key = keys[k];
for (var i in key) {
if(key[i] >= atLeast) results[k].push({"word":i, "count":key[i]});
}
}
// Result parsing
var outputHTML = []; // Buffer data. This data is used to create a table using `.innerHTML`
var f_sortAscending = function(x,y) {return y.count - x.count;};
for (k=1; k<numWords; k++) {
results[k].sort(f_sortAscending);//sorts results
// Customize your output. For example:
var words = results[k];
if (words.length) outputHTML.push('<td colSpan="3" class="num-words-header">'+k+' word'+(k==1?"":"s")+'</td>');
for (i=0,len=words.length; i<len; i++) {
//Characters have been validated. No fear for XSS
outputHTML.push("<td>" + words[i].word + "</td><td>" +
words[i].count + "</td><td>" +
Math.round(words[i].count/textlen*10000)/100 + "%</td>");
// textlen defined at the top
// The relative occurence has a precision of 2 digits.
}
}
outputHTML = '<table id="wordAnalysis"><thead><tr>' +
'<td>Phrase</td><td>Count</td><td>Relativity</td></tr>' +
'</thead><tbody><tr>' +outputHTML.join("</tr><tr>")+
"</tr></tbody></table>";
document.getElementById("RobW-sample").innerHTML = outputHTML;
/*
CSS:
#wordAnalysis td{padding:1px 3px 1px 5px}
.num-words-header{font-weight:bold;border-top:1px solid #000}
HTML:
<div id="#RobW-sample"></div>
*/

I do not know such a library in JavaScript but the logic is
split text into array
then sort and count
alternatively
split into array
create a secondary array
traversing each item of the 1st array
check whether current item exists in secondary array
if not exists
push it as a item's key
else
increase value having a key = to item sought.
HTH
Ivo Stoykov

function ngrams(seq, n) {
to_return = []
for (let i=0; i<seq.length-(n-1); i++) {
let cur = []
for (let j=i; j<seq.length && j<=i+(n-1); j++) {
cur.push(seq[j])
}
to_return.push(cur.join(''))
}
return to_return
}
> ngrams(['a', 'b', 'c'], 2)
['ab', 'bc']