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How to change swap (change) 0 to 1 in JavaScript array

Is there some nicer way how to convert 0 to 1 and vice versa in an array in JavaScript than going with for loop and converting it as described here, ie:
var variable1 = [0,1,1,0,0];
var final = []
for (var i=0; i<variable1.length; i++) {
final[i] = 1-variable1[i]
}
//1,0,0,1,1
Something similar to Python's:
[1-i for i in variable1]
# [1,0,0,1,1]
Thanks.

If you can create a new array, I'd use .map instead:
var variable1 = [0,1,1,0,0];
const final = variable1.map(n => 1 - n);
console.log(final);

You can use map to shorten the syntex.
final = variable.map(num => 1^num)
var variable = [0,1,1,0,0];
var final1 = variable.map(num => 1-num) // way one
var final2 = variable.map(num => 1^num) // way two
console.log(final1, final2)

var variable1 = [0,1,1,0,0];
var final = variable1.map(v => v ^ 1);
console.log(final);
It is also looping. but I think this code is more readable.

Javascript, adding multiple arrays to an array with a for loop

What is the best way to consolidate this code? As it is, it works perfectly, but it needs to go up to maybe 40-50 items long, so it needs to be shortened dramatically, (I assume, with a for loop).
I'm pretty much a novice when it comes to Javascript, and trying to add arrays to an array with a loop is confusing me immensely.
The "vac1.", "vac2." ...etc, variables are used later on in the code to add pointers onto a Google Maps map.
var x = count.count; // x = a value that changes (between 1 & 50)
if(x == 1){
locations = [
[vac1.vacancy_title, vac1.vacancy_latlng, vac1.vacancy_url, vac1.vacancy_location]
];
}
if(x == 2){
locations = [
[vac1.vacancy_title, vac1.vacancy_latlng, vac1.vacancy_url, vac1.vacancy_location],
[vac2.vacancy_title, vac2.vacancy_latlng, vac2.vacancy_url, vac2.vacancy_location]
];
}
if(x == 3){
locations = [
[vac1.vacancy_title, vac1.vacancy_latlng, vac1.vacancy_url, vac1.vacancy_location],
[vac2.vacancy_title, vac2.vacancy_latlng, vac2.vacancy_url, vac2.vacancy_location],
[vac3.vacancy_title, vac3.vacancy_latlng, vac3.vacancy_url, vac3.vacancy_location]
];
}
...etc etc...
I have tried using a for loop, but it doesn't work and I have no idea if I am anywhere close to figuring out how to do it correctly.
var x = count.count;
locations = [];
array = [];
for (i = 0; i < x; i++) {
array = [vac[i].vacancy_title, vac[i].vacancy_latlng, vac[i].vacancy_url, vac[i].vacancy_location];
locations.push(array);
}
Any help or advice would be greatly appreciated!
Thank you.

You need to consider them as a string:
var x = 5;
locations = [];
array = [];
for (i = 1; i <= x; i++) {
array = ['vac'+i+'.vacancy_title', 'vac'+i+'.vacancy_latlng', 'vac'+i+'.vacancy_url', 'vac'+i+'.vacancy_location'];
locations.push(array);
}
console.log(locations);

Create an array vac and use your previous code :
var x = count.count;
locations = [],
array = [],
vac = [ /* vac1, vac2, ...., vacn */ ];
for (i = 0; i < x; i++) {
array = [vac[i].vacancy_title, vac[i].vacancy_latlng, vac[i].vacancy_url, vac[i].vacancy_location];
locations.push(array);
}

You could use eval for the variable name and build an new array with another array for the wanted keys.
Basically you should reorganize yor program to use a solution without eval. An array could help. It is made for iteration.
var x = count.count,
i,
keys = ['vacancy_title', 'vacancy_latlng', 'vacancy_url', 'vacancy_location'],
locations = [];
object;
for (i = 1; i <= x; i++) {
object = eval('vac' + i);
locations.push(keys.map(function (k) { return object[k]; }));
}

Group the vac* elements in an array and then use slice to cut out as many as you want, then use map to generate the result array:
var vacs = [vac1, vac2 /*, ...*/]; // group the vacs into one single array
var x = count.count; // x is the number of vacs to generate
var locations = vacs.slice(0, x).map(function(vac) { // slice (cut out) x elements from the arrays vacs then map the cut-out array into your result array
return [vac.vacancy_title, vac.vacancy_latlng, vac.vacancy_url, vac.vacancy_location];
});

Because any global variable is a property of the global object :
var vac1 = "whatever";
console.lof(window.vac1); // => logs "whatever"
console.lof(window["vac1"]); // => accessed as an array, logs "whatever" too
You could use the global object and access it as an array to look for your vac1, vac2, vac3 variables :
var x = count.count, i;
locations = [],
array = [],
var globalObject = window; // or whatever the global object is for you
var vac; // this will be used to store your vac1, vac2, etc.
for (i = 0; i < x; i++) {
vac = globalObject["vac"+i]; // the "vac" + i variable read from the global object
if (vac !== undefined) {
array = [vac.vacancy_title, vac.vacancy_latlng, vac.vacancy_url, vac.vacancy_location];
locations.push(array);
}
}

Why does this array change its value without being asked to?

I have this array declared like this :
var gamme =
[
["A"],
["A♯","B♭"],
["B","C♭"],
["C","B♯"],
["C♯","D♭"],
["D"],
["D♯","E♭"],
["E","F♭"],
["F","E♯"],
["F♯","G♭"],
["G"],
["G♯","A♭"],
];
using this array, I’m generating another array.
I want temperamentEgal to look like this :
for example :
temperamentEgal[10] = [103.82617439498631, ["G♯","A♭"]]
temperamentEgal[25] = [233.08188075904502, ["A♯","B♭"]]
so this is what I do :
base = pow(2,1/12); // 2^(1/12)
for (i=0; i<12*octaves; i++) // octaves = 6
{
temperamentEgal[i] = []
temperamentEgal[i][0] = 55*pow(base,i); // = 138.6
temperamentEgal[i][1] = gamme[i%12]; // = ["C♯","D♭"]
console.log("gamme["+i%12+"] = " + gamme[i%12]);
for (j=0; j<temperamentEgal[i][1].length; j++)
{
var octaveNote = 1+i/12;
octaveNote = floor(octaveNote);
temperamentEgal[i][1][j] += str(octaveNote);
}
}
As you can see, at no point I’m changing the value of gamme
nonetheless, as the loop progresses, I’m getting this from the console.log :
gamme[0] = A
gamme[1] = A♯,B♭
gamme[2] = B,C♭
gamme[3] = C,B♯
gamme[4] = C♯,D♭
gamme[5] = D
gamme[6] = D♯,E♭
gamme[7] = E,F♭
gamme[8] = F,E♯
gamme[9] = F♯,G♭
gamme[10] = G
gamme[11] = G♯,A♭
gamme[0] = A1
gamme[1] = A♯1,B♭1
gamme[2] = B1,C♭1
gamme[3] = C1,B♯1
gamme[4] = C♯1,D♭1
gamme[5] = D1
gamme[6] = D♯1,E♭1
gamme[7] = E1,F♭1
gamme[8] = F1,E♯1
gamme[9] = F♯1,G♭1
gamme[10] = G1
gamme[11] = G♯1,A♭1
If I comment out temperamentEgal[i][1][j] += str(octaveNote); it’s not happening anymore.
Why would changing the value of temperamentEgal[i][1] change the value of gamme[i%12] as well ?

while you don't change gamme, you change the anonymous arrays referenced on this line:
temperamentEgal[i][1] = gamme[i%12];
both right side and left side of this assignment now point to the same Array objects - if you want to modify a copy of the Array, you should copy the values of the Array, not the reference to the Array object:
ES5: temperamentEgal[i][1] = gamme[i%12].slice();
ES6: temperamentEgal[i][1] = [...gamme[i%12]] using spread operator

Copy array --> stack or heap overflow?

I have an array named globalArrayAllTrades as you see below. I simply like to INVERT the date in a new copy of the array. So I loop through, create a new object and add it to the new array - simple.
Then function does exactly as expected. BUT if the array contains too many objects the code fails with a "FATAL ERROR: CALL_AND_RETRY_LAST Allocation failed - process out of memory".
My laptop has 8 GB of memory...When the NODEJS process crashes it uses about 1.5 GB and about 70% of of totally amount of available memory is used.
I do run the NODEJS app with the parameter: --max_old_space_size=5000 which normally fixes every thing. But not this one and i have tried MANY different ways to code the same function - BUT each and every time - it fails...unless the original array is smaller.
How can I fix this issue?
function invertTrades(){
var original = globalArrayAllTrades.slice();
globalArrayAllTrades.length = 0;
globalListAllTrades.length = 0;
for(var i = 0; i < original.length; i++){
var objS = original[i];
var objE = original[original.length-1-i];
var objInv = new TradePoint(objS.number, objS.matchdate, objE.price, objE.size, objE.issell);
globalArrayAllTrades.push(objInv);
globalListAllTrades[objInv.matchdate] = objInv;
}
}

You can save some memory by making original just contain the properties you need to invert, not the whole TradePoint object. Then you don't need to construct new TradePoint objects, you can modify them in place.
var original = globalArrayAllTrades.map(function(trade) {
return {
trade.price,
trade.size,
trade.issell
};
}).reverse();
globalArrayAllTrades.forEach(function(trade, i) {
trade.price = original[i].price;
trade.size = original[i].size;
trade.issell = original[i].issell;
});
And since all the objects were modified in place, there's no need to update globalListAllTrades.
Another way is to swap the price, size, and issell properties in place between the pairs of elements:
var midpoint = Math.floor(globalArrayAllTrade.length/2);
for (var i = 0; i < midpoint; i++) {
var objS = globalArrayAllTrades[i];
var objE = globalArrayAllTrades[globalArrayAllTrades.length-1-i];
var temp = objS.price;
objS.price = objE.price;
objE.price = temp;
temp = objS.size;
objS.size = objE.size;
objE.size = temp;
temp = objS.issell;
objS.issell = objE.issell;
objE.issell = temp;
}

Have you considered just doing this?
// Copy array and then reverse it
var newArray = [].concat(original).reverse();
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/reverse

I would suggest avoiding to copy that array:
function getInverse(i) {
var objS = globalArrayAllTrades[i];
var objE = globalArrayAllTrades[globalArrayAllTrades.length-1-i];
var objInv = new TradePoint(objS.number, objS.matchdate, objE.price, objE.size, objE.issell);
globalListAllTrades[objInv.matchdate] = objInv;
return objInv;
}
function invertTrades(){
globalListAllTrades.length = 0;
for (var i = 0, l = Math.floor(globalArrayAllTrades.length/2); i < l; i++) {
var j = globalArrayAllTrades.length-1-i;
var a = getInverse(i);
var b = getInverse(j);
globalArrayAllTrades[i] = a;
globalArrayAllTrades[j] = b;
}
}

Return array from function

--Solved by Elliot B. Thanks!
May also take int account the other modifications.
Here is the result. Thanks, everyone, for the speedy answers! http://dl.dropbox.com/u/18785762/Rust/index.html
I'm writing a game in javascript, and I want to keep the files for matching block IDs to files in a seperate .js file from the map compiler, so that I can edit things easily. However, the IDs are stored in an array, and I can't seem to get it to use the return function properly. Any help?
drawmap.js:
function drawmap() {
var images = BlockID();
var level = [
"ssssssssssssssssssssss",
"sgggggggggCCCCCdddddss",
"ssssssssss sssssss"
];
var top = 100;
var left = 100;
var mytop = top;
var myleft = left;
for (y=0; y<level.length; ++y) {
var row = level[y];
for (x=0; x < row.length; ++x) {
var c = row.charAt(x);
if(c != ' ') {
img_create(images[c], mytop, myleft);
}
mytop += 13;
myleft += 27;
}
mytop = top + (y+1)*13;
myleft = left - (y+1)*27;
}
}
mapread.js:
function BlockID() {
var IDs = new Array();
images['s'] = "Images/Block_01.png";
images['g'] = "Images/Block_02.png";
images['C'] = "Images/Block_03.png";
images['d'] = "Images/Block_04.png";
return IDs;
}

At a minimum, change this:
function BlockID() {
var IDs = new Array();
images['s'] = "Images/Block_01.png";
images['g'] = "Images/Block_02.png";
images['C'] = "Images/Block_03.png";
images['d'] = "Images/Block_04.png";
return IDs;
}
To this:
function BlockID() {
var IDs = new Object();
IDs['s'] = "Images/Block_01.png";
IDs['g'] = "Images/Block_02.png";
IDs['C'] = "Images/Block_03.png";
IDs['d'] = "Images/Block_04.png";
return IDs;
}
There are a couple fixes to point out. First, images is not defined in your original function, so assigning property values to it will throw an error. We correct that by changing images to IDs. Second, you want to return an Object, not an Array. An object can be assigned property values akin to an associative array or hash -- an array cannot. So we change the declaration of var IDs = new Array(); to var IDs = new Object();.
After those changes your code will run fine, but it can be simplified further. You can use shorthand notation (i.e., object literal property value shorthand) to create the object and return it immediately:
function BlockID() {
return {
"s":"Images/Block_01.png"
,"g":"Images/Block_02.png"
,"C":"Images/Block_03.png"
,"d":"Images/Block_04.png"
};
}

Your BlockID function uses the undefined variable images, which will lead to an error. Also, you should not use an Array here - JavaScripts key-value-maps are plain objects:
function BlockID() {
return {
"s": "Images/Block_01.png",
"g": "Images/Block_02.png",
"C": "Images/Block_03.png",
"d": "Images/Block_04.png"
};
}

neater:
function BlockID() {
return {
"s":"Images/Block_01.png",
"g":"Images/Block_02.png",
"C":"Images/Block_03.png",
"d":"Images/Block_04.png"
}
}
or just
var images = {
"s":"Images/Block_01.png",
"g":"Images/Block_02.png",
"C":"Images/Block_03.png",
"d":"Images/Block_04.png"
}

Taking in consideration that in JavaScript Array is object too this can be written as:
function BlockID() {
return new Array(
"Images/Block_01.png",
"Images/Block_02.png",
"Images/Block_03.png",
"Images/Block_04.png"
);
}
This code will display content of array in browser's window
window.onload=function(){
var s="";
var ar = BlockID(); //function return array
for(el in ar){
s+=ar[el]+"</br>";
}
document.body.innerHTML=s;
};