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Print elements of object array in Javascript

I have this array of objects to count element frequency in another array using for loop which prints correct output.
counts = {};
counter = 0;
counter_array = [50,50,0,200]; //this is just for example, this array is filled dynamically
for (var x = 0, y = counter_array.length; x < y; x++) {
counts[counter_array[x]] = (counts[counter_array[x]] || 0) + 1;
}
console.log('FREQUENCY: ',counts); //outputs FREQUENCY: {50:2, 0:1, 200:1}
There is another array of arrays:
holder_text_array = [["a",50,0],["b",0,0]]; //example of dynamically filled array
var p = "a";
var i = 0;
while(i < holder_text_array.length){
if (holder_text_array[i][0]==p) {
var s = counts[holder_text_array[i][1]];
console.log('Element: ', holder_text_array[i][1]); //prints 50 for i = 0
console.log('frequency: ',counts[s]); //prints undefined
counter = counts[s];
}
i++;
}
The array of arrays "holder_text_array" consists of elements whose frequency I need to get in the while loop. Can someone tell me where am I wrong?

The frequency is stored in s not in counts[s]
You're logging counts[s] where var s = counts[holder_text_array[i][1]];
You've already got the element from counts in s. Just log the value of s
Apart from that the function works!
counts = {};
counter = 0;
counter_array = [50,50,0,200]; //this is just for example, this array is filled dynamically
for (var x = 0, y = counter_array.length; x < y; x++) {
counts[counter_array[x]] = (counts[counter_array[x]] || 0) + 1;
}
console.log('FREQUENCY: ',counts); //outputs FREQUENCY: {50:2, 0:1, 200:1}
holder_text_array = [["a",50,0],["b",0,0]]; //example of dynamically filled array
var p = "a";
var i = 0;
while(i < holder_text_array.length){
if (holder_text_array[i][0]==p) {
var s = counts[holder_text_array[i][1]];
console.log('Element: ', holder_text_array[i][1]); //prints 50 for i = 0
console.log('frequency: ', s); // CHANGED THIS TO JUST `s`
counter = counts[s];
}
i++;
}

You could take a recursive approach and call the count function again for (nested) arrays with the same counts object.
The result contains the counts of each element.
function getCounts(array, counts = {}) {
for (let i = 0; i < array.length; i++) {
const value = array[i];
if (Array.isArray(value)) {
getCounts(value, counts);
continue;
}
if (!counts[value]) counts[value] = 0;
counts[value]++;
}
return counts;
}
console.log(getCounts([["a", 50, 0], ["b", 0, 0]]));

I figured out the problem. Issue is in initialization.
I changed the following:
var s = counts[holder_text_array[i][1]];
counter = counts[s];
It works this way:
var s = holder_text_array[i][1];
counter = counts[s];

Google Apps Scripts setValues() incorrect height error

I've looked at some other questions similar to this, but I'm getting my array in a unique way and I can't figure out for the life of my how to change it to a 2D array.
//Special function for adding arrays, just use sumArray on first array with second array in parenthesis
//==========================================
Array.prototype.sumArray = function (arr) {
var sum = this.map(function (num, idx) {
return num + arr[idx];
});
return sum;
}
var array1 = [1,2,3,4];
var array2 = [5,6,7,8];
var sum = array1.sumArray(array2);
Logger.log("sum: " + sum);
//==========================================
var calc = ss.getRangeByName( "calc" );
var target = ss.getRangeByName( "target" );
var current = ss.getRangeByName( "current" );
var left = ss.getRangeByName( "left" );
var gainedEVs = calc.getValues();
var goalEVs = target.getValues();
var oldEVs = current.getValues();
var leftEVs = left.getValues();
//Make everything ints
//==========================================
for(var i = 0; i < oldEVs.length; i++) {
Logger.log(oldEVs.length);
oldEVs[i] = parseInt(oldEVs[i]);
}
for(var i = 0; i < gainedEVs.length; i++) {
gainedEVs[i] = parseInt(gainedEVs[i]);
}
for(var i = 0; i < goalEVs.length; i++) {
goalEVs[i] = parseInt(goalEVs[i]);
}
for(var i = 0; i < leftEVs.length; i++) {
leftEVs[i] = parseInt(leftEVs[i]);
}
//==========================================
var newEVs = [[oldEVs.sumArray(gainedEVs)]];
var newLeft = [[goalEVs.subArray(newEVs)]];
//Now I try to set values and I get the error
current.setValues(newEVs);
I've tried changing the setValues to setValues([newEVs]); but that doesn't work either. Any clue on how I can get my array of newEVs to be the correct height? It has the right number of values, but those values are being stored in columns, not rows. (in this case all of my ranges are 6 rows 1 col)

Since your ranges are small, you don't have to worry too much about performance, so you can convert them from rows to columns using a loop:
var column = [];
for (var i=0; i<newEVs.length; i++){
column.push([newEVs[i]]);
}
current.setValues(column);

Defining a 3D array in JavaScript

I tried to define a 3D array on Google Sheet, but even though I'm using the .slice() method it keeps passing the array by reference.
var temp = [];
for (var a = 0; a<archetypesAll.length; a++) {temp[a] = [0, a].slice();};
var archRank = [];
for (var a = 0; a<21; a++) {archRank[a]= temp.slice();};
archRank[2][1][0] = 'Test';
I want to edit a single element of the matrix but instead the code above just fills every row with the exact same value ('Test'):
3DMatrix[x][1][0] = 'Test'

You can't just copy a multidimensional array by calling slice at the top level, because that will not deep-copy the whole. You have to write your own deepCopy methid, like this:
function allocate(mainDim, ...dims) {
const result = new Array(mainDim);
for (let i = 0; i < result.length; i++) {
result[i] = dims.length > 0 ? allocate(...dims) : 0;
}
return result;
}
function deepCopy(matrix, dims) {
return dims > 1 ? matrix.map(row => deepCopy(row, dims - 1)) : matrix.slice();
}
function test() {
const mx1 = allocate(3,2,2);
mx1[2][1][0] = "Test";
console.log(JSON.stringify(mx1));
const mx2 = deepCopy(mx1, 3);
mx2[2][1][0] = "Copied";
console.log(JSON.stringify(mx1));
console.log(JSON.stringify(mx2));
}
test();

var array = ["Test", "Test"];
var array3d = [[array.slice(0)],[[array.slice(0)]]];
array3d[0][0][0] = "Changed";
console.log(JSON.stringify(array3d)); //[[["Changed","Test"]],[[["Test","Test"]]]]
Try with this instead of slice to get a new array instead of reference:
var temp = [];
for (var a = 0; a < archetypesAll.length; a++) {
temp[a] = JSON.parse(JSON.stringify([0, a]));
}
var archRank = [];
for (var a = 0; a < 21; a++) {
archRank[a]= temp.slice();
}
archRank[2][1][0] = 'Test';

Alternately Join 2 strings - Javascript

I have 2 strings and I need to construct the below result (could be JSON):
indexLine: "id,first,last,email\n"
dataLine: "555,John,Doe,jd#gmail.com"
Result: "id:555,first:john,....;
What would be the fastest way of joining alternately those 2 strings?
I wrote this - but it seems too straight forward:
function convertToObject(indexLine, dataLine) {
var obj = {};
var result = "";
for (var j = 0; j < dataLine.length; j++) {
obj[indexLine[j]] = dataLine[j]; /// add property to object
}
return JSON.stringify(obj); //-> String format;
}
Thanks.

var indexLine = "id,first,last,email";
var dataLine = "555,John,Doe,jd#gmail.com";
var indexes = indexLine.split(',');
var data = dataLine.split(',');
var result = [];
indexes.forEach(function (index, i) {
result.push(index + ':' + data[i]);
});
console.log(result.join(',')); // Outputs: id:555,first:John,last:Doe,email:jd#gmail.com

If you might have more than one instance of your object to create, you could use this code.
var newarray = [],
thing;
for(var y = 0; y < rows.length; y++){
thing = {};
for(var i = 0; i < columns.length; i++){
thing[columns[i]] = rows[y][i];
}
newarray.push(thing)
}
source

Looping through an array to create an object in Javascript

I want to write a function that takes an array such as:
var columns = ['distance', 'times', 'acceleration']
Then from this array, I want to generate something like this:
[{id: id_0, distance: 0, times: 0, acceleration: 0}, {id: id_1, distance: 1, times: 1, acceleration: 1}]
Notice that we have 2 objects here, but I want it to be whatever number I pass in to my parameter. Here is what I have:
generateData: function(rows, columns) {
var generatedData = [];
for (var i = 0, rowLen = rows.length; i < rowLen; i++) {
for (var n = 0; i < columns.length; n++) {
// not sure how to construct an object here from looping through my columns array
generatedData.push({
id: 'id_ + n',
// confused here
});
}
return generatedData;
}
}

This is the perfect place to dynamically create your own function. Try this:
function createArrayOfObjects(columns, count) {
var objectProps = new Array(columns.length);
for (var i = 0; i < columns.length; i++){
//":j" will be the variable j inside the dynamic function
objectProps[i] = columns[i] + ":j";
}
var funcBody = "var arr = new Array(count);" +
"for(var j = 0; j < count; j++){" +
"arr[j] = {" + objectProps.join(',') + "};" +
"}" +
"return arr;";
//Create a new function and call it with count as the parameter, returning the results
return new Function("count", funcBody)(count);
}
var count = 10;
var columns = ['distance', 'times', 'acceleration'];
createArrayOfObjects(columns.concat('id'), count);
This has the benefit of only having to loop over the columns array once where other solutions require nested loops.
JSPerf

I am giving you away the initial non-optimized solution. Its upto you to do the optimizations.
generateData: function(rows, columns) {
var generatedData = [];
for (var i = 0; i < rows.length; i++) {
var myObj = {};
myObj["id_" + i] = i;
for (var n = 0; n < columns.length; n++) {
myObj[columns[n]] = i;
}
generatedData.push(myObj);
}
return generatedData;
}

A functional approach that will take the object properties from the passed in array, instead of hard-coding them, might look something like this inside the for loop to populate an array named 'rows' with property names coming from the values of an array named 'cols':
cols.forEach(function(cv, ci, ca) { rows[ri][cv] = ri; });
See the snippet for a full example. Note that, in this example, I'm just shoving the current index of "rows" into the object as the property value.
var columns = ['distance', 'times', 'acceleration'];
function generateData(numRows, cols) {
rows = new Array(numRows);
for(ri=0; ri < rows.length; ri++) {
rows[ri] = { id: ri };
cols.forEach(function(cv, ci, ca) {
rows[ri][cv] = ri;
});
}
return rows;
}
data = generateData(5, columns);
console.log(data);