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I Failed To Train Neural Network On JS

I am newbie in machine learning, but decided to make own js library for neural networks, everything went perfect until i tryed to train my NN. In My Mini Library i created some functions...
1) A Function That Creates My Neuron-Object:
this.Node = function (conns) {
var output = {};
output.b = hyth.Random({type: "TanH"});
output.w = [];
for (var a = 0; a < conns; a++){
output.w[a] = hyth.Random({type: "TanH"});
}
output.Value = function (i) {
if (i.length == conns) {
var sum = 0;
for (var a = 0; a < conns; a++){
sum += i[a] * output.w[a];
}
sum += output.b;
return myMath.Activate(sum, {type: "Sigmoid"});
}
}
return output;
}
This function has one argument , which is the amount of wanted weights from neuron, and it returns an object with two properties - "b" the float (bias), and "w" the 1D Array which contains floats, and one method - which calculates the activation of neuron-object.
2) A Function That Creates My Neural Net
this.Network = function () {
var p = arguments;
var arr = [];
for (var a = 0; a < p.length-1; a++){
arr[a] = [];
for (var b = 0; b < p[a+1]; b++){
arr[a][b] = this.Node(p[a]);
}
}
return arr;
}
This Function Returns A 2D Array with Neuron-Object as It's final value, using argument array as settings for layer count and node count for each layer.
3) A Function That Feeds Forward The NN
this.Forward = function (network, input) {
if (network[0][0].w.length == input.length) {
var activations = [];
for (var a = 0; a < network.length; a++){
activations[a] = [];
for (var c = 0; c < network[a].length; c++){
if (a == 0){
activations[0][c] = network[0][c].Value(input);
continue;
}
activations[a][c] = network[a][c].Value(activations[a-1]);
}
}
return activations;
}
}
This Function Returns 2D array with an activation float for every neuron as it's final value. It uses 2 agruments - the output of 2nd function, input array.
4) And Final Function That Backpropagates
this.Backward = function (network, input, target) {
if (network[0][0].w.length == input.length && network[network.length-1].length == target.length) {
var activations = this.Forward(network, input, true);
var predictions = activations[activations.length-1];
var errors = [];
for (var v = 0; v < network.length; v++) {
errors[v] = [];
}
for (var a = network.length-1; a > -1; a--){
for (var x = 0; x < network[a].length; x++) {
var deract = hyth.Deractivate(activations[a][x]);
if (a == network.length-1) {
errors[a][x] = (predictions[x] - target[x]) * deract;
} else {
errors[a][x] = 0;
for (var y = 0; y < network[a+1].length; y++) {
errors[a][x] += network[a+1][y].w[x] * errors[a+1][y];
}
errors[a][x] *= deract;
}
}
}
return errors;
}
}
This Function Returns 2D array with the rror float for every neuron as it's final value. Arguments are 3 - the nnet , input and wanted output.
So I can make a neural network, feed forward and and backpropagate, receive activations and errors, but i always fail to train my net with my errors and activations to work perfect , last time it was outputing same result for every type of input. I want to understand training algorithm from zero , so i need someone's help.
P.S. - i dont want someone say that i need to use famous libraries , i want to understand and make it myself.

How to step through google script

I am trying to write a Google Sheets script macro. How do I step through it to understand why the time is being exceeded?
My problem is the loop, when I set the iteration max(scenarios) to 46, the code seems to run fine, taking about 1-2 seconds. When the max is set to 47, it dies with max execution time exceeded (4-5 minutes). Whats going on?
function testing() {
var aa = SpreadsheetApp.getActiveSpreadsheet().getSheetByName("Run
Program");
var scenarios = aa.getRange("H19").getValue();
for (i = 1; i <= scenarios; i++){
var ss =
SpreadsheetApp.getActiveSpreadsheet().getSheetByName("Sheet6");
var range = ss.getRange("b6:u6");
var min = 1 ;
var max = 20 ;
var numbers = []
for (var i = min; i <= max; i++) {
numbers.push(i);
}
shuffleArray(numbers)
var counter = 0;
for (var x = 1; x <= range.getWidth(); x++) {
for (var y = 1; y <= range.getHeight(); y++) {
range.getCell(y, x).setValue(numbers[counter]);
counter++;
}
}
var range = ss.getRange("v6:ao6");
var min = 21 ;
var max = 40 ;
var numbers = []
for (var i = min; i <= max; i++) {
numbers.push(i);
}
shuffleArray(numbers)
var counter = 0;
for (var x = 1; x <= range.getWidth(); x++) {
for (var y = 1; y <= range.getHeight(); y++) {
range.getCell(y, x).setValue(numbers[counter]);
counter++;
}
}
var range = ss.getRange("ap6:at6");
var min = 41 ;
var max = 45 ;
var numbers = []
for (var i = min; i <= max; i++) {
numbers.push(i);
}
shuffleArray(numbers)
var counter = 0;
for (var x = 1; x <= range.getWidth(); x++) {
for (var y = 1; y <= range.getHeight(); y++) {
range.getCell(y, x).setValue(numbers[counter]);
counter++;
}
}
}
// function Chart4() {
var spreadsheet = SpreadsheetApp.getActive();
spreadsheet.getRange('A1').activate();
spreadsheet.getSheetByName('Chart4').showSheet()
.activate();
spreadsheet.setActiveSheet(spreadsheet.getSheetByName('Chart4'),
true);
};

Your code needs a lot of help. Here's a tip to get you started.
As others have mentioned, you should call .getValues() on the whole range, which gives you a 2 dimensional array of cell values [[A1value,B1value,...],[A2val,B2val...],...]. You should grab the width and length first and assign to a variable. Reference that variable instead of calling the API in the loop conditions. In fact, since you know the ranges ahead of time, you should define all the ranges you'll be needing outside of the main for loop, as well as the spreadsheet (ss):
var aa = SpreadsheetApp.getActiveSpreadsheet().getSheetByName("Run Program");
var ss = SpreadsheetApp.getActiveSpreadsheet().getSheetByName("Sheet6");
var range1 = ss.getRange("b6:u6");
var range2 = ss.getRange("v6:ao6");
for (i = 1; i <= scenarios; i++) { ...
Scripts start taking a long time if you make repeated calls to the API.
Not sure exactly what your macro is trying to do, but here is a template for running this kind of loop and how you should think about it.
var range = ss.getRange(A1-style-address);
var values = range1.getValues();
var width = range1[0].length;
var height = range1.length;
var new_values = new Array();
for (var i = 0; i < height; i++) {
for (var j = 0; j < width; j++) {
//do something with values[i][j], like push to new_values
}
}
//something like:
//var new_range = ss.getRange(different A1-style address)
//new_range.setValues(new_array)
You'll have to make sure that the new array contains values in a 2 dimensional array that has the same dimensions as the range you're putting them into or it will throw an error.
I'll leave it to you to figure out how to modify the new_values array inside the loop to make sure it is the right size.
Here's a link to an overview of arrays in javascript if this is new for you, and here's some array documentation.

Range.getCell() call can be expensive sometimes and should be avoided. Use Range.getValues() and iterate over the two dimensional array. Also, instead of using active spreadsheet open spreadsheet by Id for unit testing. This way you will be able to debug/run from GAS editor directly. GAS editor usually catches such performance issues in the code and displays warnings pointing to the line number in the code.

Strange performance quirk in javascript

I experience a strange differences in performance of simple task depending of array I am working with. The task is to calculate sum of those elements in array which are greater than 5. Task is performed on arrays with equal lenghts.
I try the very same approach on three different array objects:
1) var hugeArray1 - array with all elemenets randomly picked from 0:10 range
2) var hugeArray2 - copy of hugeArray1 sorted with Array.prototype.sort()
3) var hugeArray3 - handcrafted but sorted array with values from 0:10 range, spread to equaly cover this interval.
I try to calculate sum of elements greater than 5 many times for each Array and then average them. What is strange, time needed varies a lot for those three arrays.
1) hugeArray1: 5.805ms
2) hugeArray2: 15.738ms
3) hugeArray3: 3.753ms
Result for array sorted with sort() is extreamly poor. Why is that? it looks like sort() returns some kind of wraper/proxy instead of 'native' Array, which affects performance. I tried it on 2 computers. Also i tried to change order of testing.
I include code below, please tell me what is happening here.
// random array with elements 0-10 of size n
function randomArray(n) {
var arr = [];
for (var i = 0; i < n; ++i) {
arr.push(Math.random() * 10);
}
return arr;
};
// measures time of execution
function measureTime(f) {
var start = new Date().getTime();
f();
var stop = new Date().getTime();
return stop - start;
};
// enumerate ofer array and calculate sum of elementsgreater than 5
function sumGreaterThan5(arr) {
var sum = 0;
for (var i = 0; i < arr.length; ++i) {
if (arr[i] > 5.0)
sum += arr[i];
}
return sum;
}
// generate array os size 'size' with elements with constant step to fill interval 0:10
function generateSortedArr(size) {
var arr = [];
for (var i = 0; i < size; ++i) {
arr.push(i * 10 / size);
}
return arr;
}
var huge = 1000000;
var hugeArray1 = randomArray(huge);
var hugeArray2 = hugeArray1.slice(0).sort();
var hugeArray3 = generateSortedArr(huge);
var hugeArrays = [hugeArray1, hugeArray2, hugeArray3];
hugeArrays.forEach(x=> {
var res = [];
for (var i = 0; i < 1000; ++i) {
res.push(measureTime(function () {
sumGreaterThan5(x);
}));
}
console.log(res.reduce((prev, curr)=> prev + curr) / res.length);
});
// random array with elements 0-10 of size n
function randomArray(n) {
var arr = [];
for (var i = 0; i < n; ++i) {
arr.push(Math.random() * 10);
}
return arr;
};
// measures time of execution
function measureTime(f) {
var start = new Date().getTime();
f();
var stop = new Date().getTime();
return stop - start;
};
// enumerate ofer array and calculate sum of elementsgreater than 5
function sumGreaterThan5(arr) {
var sum = 0;
for (var i = 0; i < arr.length; ++i) {
if (arr[i] > 5.0)
sum += arr[i];
}
return sum;
}
// generate array os size 'size' with elements with constant step to fill interval 0:10
function generateSortedArr(size) {
var arr = [];
for (var i = 0; i < size; ++i) {
arr.push(i * 10 / size);
}
return arr;
}
var huge = 1000000;
var hugeArray1 = randomArray(huge);
var hugeArray2 = hugeArray1.slice(0).sort();
var hugeArray3 = generateSortedArr(huge);
var hugeArrays = [hugeArray1, hugeArray2, hugeArray3];
hugeArrays.forEach(function(x){
var res = [];
for (var i = 0; i < 1000; ++i) {
res.push(measureTime(function () {
sumGreaterThan5(x);
}));
}
console.log(res.reduce(function(prev, curr){return prev + curr},0) / res.length);
});

How to make a function that makes an array?

I am trying to make a function that generates an array of numbers within a certain range.
A very basic question but I couldn't find an explanation...
I tried this
var newArray = [];
function makeArrey(start, last) {
var length = last - start;
for(var i = 0; i <= length; i++) {
newArray[i] = start + i;
}
return newArray;
}
makeArrey(1, 100);
alert(newArray[4]); //4 is a random number to see if it works, it dont work

Your code is working perfectly fine. You're just forgetting that arrays start at index 0. So when you do something like newArray[4] it returns the 5th element of the array, which is 5 in your case.
For the sake of fixing your code so that it behaves nicer, do this:
function makeArray(start, last) {
var range = [];
var length = last - start;
for(var i = 0; i <= length; i++) {
range[i] = start + i;
}
return range;
}
var newArray = makeArray(1, 100);

Randomly storing elements from an array into a table

I'm trying to create a simple memory matching game and I'm having trouble assigning one number to each table cell from my cardValues array. My giveCellValue function is supposed to generate a random number then pick that number from the array and give it to one of the table cells but I'm a little over my head on this one and having trouble accomplishing this task.
var countCells;
var cardValues = [];
var checker = true;
var createTable = function (col, row) {
$('table').empty();
for (i = 1; i <= col; i++) {
$('table').append($('<tr>'));
}
for (j = 1; j <= row; j++) {
$('tr').append($('<td>'));
}
countCells = row * col;
};
createTable(3, 6);
for (i = 1; i <= countCells / 2; i++) {
cardValues.push(i);
if (i === countCells / 2 && checker) {
checker = false;
i = 0;
}
}
var giveCellValue = function () {
var random = Math.ceil(Math.random() * cardValues.length) - 1;
for (i = 0; i <= cardValues.length; i++) {
$('td').append(cardValues[random]);
cardValues.splice(random, 1);
}
};
giveCellValue();
console.log(cardValues);

Use
var countCells;
var cardValues = [];
var checker = true;
var createTable = function (col, row) {
$('table').empty();
for (var i = 0; i < col; i++) {
$('table').append($('<tr>'));
}
for (var j = 0; j < row; j++) {
$('tr').append($('<td>'));
}
countCells = row * col;
};
createTable(3, 6);
for (i = 0; i < countCells; i++) {
cardValues.push(i % 9 + 1);
}
var giveCellValue = function () {
var len = cardValues.length, tds = $('td');
for (var i = 0; i < len; i++) {
var random = Math.floor(Math.random() * cardValues.length);
tds.eq(i).append(cardValues.splice(random, 1));
}
};
giveCellValue();
console.log(cardValues);
Demo: Fiddle

Leaving aside the problems that have already been mentioned in the comments above...
If I understand it right, you want to assign each of the numbers in cardValues to a random table cell?
Seems like the problem is with this line:
var random = Math.ceil(Math.random() * cardValues.length) - 1;
What this does is generates a random number once. If you access the variable random at a later time, you're not calling the full line of code again, you're just getting the same value that was calculated the first time. E.g. if the above code runs, spits out '7' as its random number and stores that in random, then every time you go through the for loop, the value of random will always be '7' rather than being re-generated every time - make sense?
Try putting the randomiser inside the for loop - that way it will be run multiple times, generating a new random number every time:
var giveCellValue = function () {
var random;
for (i = 0; i <= cardValues.length; i++) {
random = Math.ceil(Math.random() * cardValues.length) - 1;
$('td').append(cardValues[random]);
cardValues.splice(random, 1);
}
};
Actually, I'd change line 4 above to random = Math.floor(Math.random() * cardValues.length); too which should have the same effect.