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Accessing an objects property inside a function

I'm trying to access objects properties inside an array in my code to render the text values of input boxes restored after a refresh from the local storage but for some reason when I try to run the for loop inside my appStart() function it gives me: "Uncaught TypeError: Cannot read property 'id' of undefined at appStart". Any insiights of why this happens and how to fix it will be greatly appreciated.
const currentDayPlaceholder = $("#currentDay");
const timeInTimeBlocks = $(".input-group-text");
const timeBlockInput = $(".form-control");
const saveButton = $(".saveBtn");
let numericCurrentTime = parseInt(moment().format("H A"));
let notes = [];
currentDayPlaceholder.append(moment().format('dddd, MMMM Do'));
function timeBlocksColorDeterminator() {
for (let i = 0; i < timeInTimeBlocks.length; i++) {
let numericTimeinTimeBlock = parseInt($(timeInTimeBlocks[i]).text());
if ($(timeInTimeBlocks[i]).hasClass('pm')) {
numericTimeinTimeBlock += 12;
}
if (numericCurrentTime === numericTimeinTimeBlock) {
$(timeBlockInput[i]).addClass("present");
} else if (numericCurrentTime > numericTimeinTimeBlock) {
$(timeBlockInput[i]).addClass("past");
} else {
$(timeBlockInput[i]).addClass("future");
}
}
}
function appStart() {
notes = JSON.parse(localStorage.getItem("timeBlockNotes"));
for (let i = 0; i < timeBlockInput.length; i++) {
if (i === parseInt(notes[i].id)) {
timeBlockInput[i].value = notes[i].value;
}
}
}
appStart();
saveButton.on("click", function () {
console.log("click");
notes.push({
value: timeBlockInput[this.id].value,
id: this.id
})
localStorage.setItem("timeBlockNotes", JSON.stringify(notes));
})
timeBlocksColorDeterminator();

I have fixed this after changing my appStart() function to this :
function appStart() {
notes = JSON.parse(localStorage.getItem("timeBlockNotes"));
for (let i = 0; i < notes.length; i++) {
timeBlockInput[parseInt(notes[i].id)].value = notes[i].value;
}
}
thank you guys for your comments and answers.

neural network backprop algorithm implementation question

I've been writing a neural network from scratch to learn from.
but since i'm still learning - I want to make sure what I'm writing is actually correct.
I have an array of arrays (a matrix), of cell objects. attached to a 'brain' object which has the following method two methods:
train: function(data)
{
for (let b=0; b< data.length; b++)// for the length of the training data - I.E. we are going assume we are getting many relatively shortly indexed arrays
{
if(data[b].answers.length != data[b].questions.length)
{
console.log("bad data");
return false;
}
for(let c=0;c<data[b].questions.length;c++)
{
brain.attachInputLayer(data[b].questions[c]);
brain.updateForward();
let direction = brain.determinDirection(data[b].answers[c]); //return an array of updateObject with determined weights bias value adjustments, which each cell gets updated order should be from generation by column;
brain.cellMatrix.forEach(cellArray=> cellArray.forEach(cell=> cell.adjust(direction.find(x=> x.ID ===cell.ID))));
brain.updateForward();
brain.displayBrain();
}
}
console.log("all training data done");
alert("win?");
console.log(brain.cellMatrix);
console.log("brain");
}
and
determinDirection:function(answer)
{
// answer is the array of values of each answer cell we want as a result
let arrayOfUpDateObjectsForCell = [];
for(let e=0; e<answer.length; e++)
{
let answerCell = brain.cellMatrix[cellMatrix.length-1][e];
let returnBucket = [];
arrayOfUpDateObjectsForCell.push(answerCell.whatIwant(answer[e], returnBucket));
}
let list = Flat(arrayOfUpDateObjectsForCell);
let realList = Clean(list);
return realList;
}
so each cell of the last generation (the answer output) calls the whatIwant method at brain.train(), this function propagates backwards through the network... but my question really is this:::
:::
does it look like I am calculating the error / direction to move each value correctly?
is averaging the changes between the duplicated updateObjects correct?
(the desiredObjectchange for cell.gen=3,order=0 gets created from each of the next layer cells calling whatIwant. the changes cell.gen=4,order=0 wants cell.gen=3,order=0 to have is averaged with the changes cell.gen=4,order=1 wants for cell.gen=3,order=0).
is averaging the correct operation here?
:::
whatIwant:function(answerValue, returnArray)
{
let desiredWeights = this.weights;
let desiredBias = this.bias;
let desiredActivations = this.activations;
let error = (1/2)*Math.pow(cell.value-answerValue,2);
let desiredObjectChange =
{
ID:this.ID,
weights:this.weights,
bias:this.bias,
activations:this.activations,
value:answerValue,
combine:function(yourCloneFriend)
{
if(yourCloneFriend == false)
{
return;
}
this.bias = (1/2)*(this.bias+yourCloneFriend.bias);
let cWeight = yourCloneFriend.weights[Symbol.iterator]();
let cActivations = yourCloneFriend.activations[Symbol.iterator]();
this.weights.forEach(x=> (1/2)*(x+cWeight.next().value));
this.activations.forEach(y=> (1/2)*(y+cActivations.next().value));
this.recalculateValue();
return this;
},
recalculateValue:function()
{
this.value = Sigmoid(arrayMultiply(this.weights, this.activations)+this.bias);
}
}
for(let k = 0; k< this.weights.length; k++)
{
let lastValue = Sigmoid(arrayMultiply(desiredWeights, desiredActivations)+desiredBias);
let lastError = (1/2)*Math.pow(lastValue-answerValue,2);
for(let l=0;l<3;l++)
{
let currentValue = Sigmoid(arrayMultiply(desiredObjectChange.weights, desiredObjectChange.activations)+desiredObjectChange.bias);
let currentError = (1/2)*Math.pow(currentValue-answerValue,2);
let positiveRange = false;
if(desiredWeights[k] < 0){ positiveRange = true;}
let nudgedWeightArray = NudgeArray(desiredWeights, k, l, positiveRange); //returns a copy array to test, with weight adjusted.
let testWeightChange = Sigmoid(arrayMultiply(nudgedWeightArray,desiredActivations)+desiredBias);
let testWeightError = (1/nudgedWeightArray.length)*Math.pow(testWeightChange - answerValue, 2);
let testWeightResult = compareSmallnumbers('isSmaller', currentError, testWeightError);
if(testWeightResult);
{
desiredWeights = nudgedWeightArray;
currentError = testWeightError;
}
positiveRange=false;
if(desiredBias < 0){positiveRange = true;}
let nudgedBiasVal = this.nudge(desiredBias,l,positiveRange);
let testBiasChange = Sigmoid(nudgedBiasVal+desiredWeights[k]*desiredActivations[k]);
let testBiasError = (1/1)*Math.pow(testBiasChange - answerValue, 2);
let testBiastResult = ('isSmaller', currentError, testBiasError);
if(testBiastResult);
{
desiredBias = nudgedBiasVal;
currentError = testBiasError;
}
positiveRange=!!Math.random(0,1)>5;
let nudgedAcitivationArray = NudgeArray(desiredActivations,k,l,positiveRange);
let testActivationChange = Sigmoid(arrayMultiply(nudgedAcitivationArray,desiredWeights)+desiredBias);
let testActivationError = (1/nudgedAcitivationArray.length)*Math.pow(testActivationChange - answerValue, 2);
let testActivationResult = compareSmallnumbers('isSmaller', currentError, testActivationError);
if(testActivationResult);
{
desiredActivations[k] = nudgedAcitivationArray[k];
currentError = testActivationError;
}
//and the end of the loop, update the error to the new value
let errorResult = compareSmallnumbers('isSmaller',lastError, currentError);
if(errorResult)
{
lastError = currentError;
}
}
desiredObjectChange.weights[k] = desiredWeights[k];
desiredObjectChange.bias = desiredBias;
desiredObjectChange.activations[k] = desiredActivations[k];
desiredObjectChange.value = Sigmoid(arrayMultiply(desiredObjectChange.weights, desiredObjectChange.activations)+desiredObjectChange.bias);
}
let combineObject = returnArray.find(x=>x.ID === desiredObjectChange.ID);
if(!combineObject)
{
returnArray.push(desiredObjectChange);
}
//that was this object - simple stuff, now we need to call this function
if(Array.isArray(cell.lastGenerationTargetKeys) && cell.lastGenerationTargetKeys.length)
{
let nextActivation = desiredObjectChange.activations[Symbol.iterator]();
brain.cellMatrix[cell.generation-1].forEach(x=> x.whatIwant(nextActivation.next().value, returnArray));
return returnArray;
}
else
{
return;
}
},
clean,flat and NudgeArray are these::
function Clean(array)
{
let rArray = [];
array.forEach((x)=>
{
let search = rArray.find(y=>y.ID ===x.ID);
if(search === undefined)
{
rArray.push(x);
}
else
{
rArray[rArray.indexOf(search)].combine(x);
}
});
return rArray;
}
function Flat(array)
{
let holdBucket = [];
let flatten = function(array)
{
for(let i = 0; i<array.length;i++)
{
if(Array.isArray(array[i]))
{
flatten(array[i]);
}
else
{
holdBucket.push(array[i]);
}
}
}
flatten(array);
return holdBucket;
}
function NudgeArray(array ,arrayIndex, Nudgeindex, isPositive)
{//nudge index is designed to act like a variable learning rate modifier, as it tests, jumps decrease in size
let returnArray = [];
array.forEach(x=>returnArray.push(x));
let value = returnArray[arrayIndex];
if(isPositive)
{
value+=(Math.random(0,1)/(Nudgeindex+3));
value = Sigmoid(value);
}
else
{
value+=(Math.random(-1,1)/(Nudgeindex+3));
value = Sigmoid(value);
}
returnArray.splice(arrayIndex,1,value);
return returnArray;
}

Firebase Promise in For Loop

I've a situation where I've to get the object based on each item in for loop, after getting that object I've to make another for loop to get object for that item. How to i create a promise for this? For reference, you can check my code below:
for(var i = 0 ; i < children.length ; i++)
{
firebaseref = firebase.database().ref(children[i]);
var parentRef = firebaseref.once('value').then(function(snapshot){
var childRef;
if(snapshot.val().userRef!=undefined){
var keys = Object.keys(snapshot.val().userRef);
for(var i = 0; i < keys.length ; i++){
if(Is_static==true){
childRef = firebase.database().ref(keys[i]);
}
else{
childRef = firebase.database().ref(keys[i]);
}
childRef = childRef.once('value').then(function(snapshot){
var email = snapshot.val().email;
var mob = snapshot.val().mob;
if(email!=undefined && email!=""){
if(emails.indexOf(email)==-1)
emails.push(email);
}else if(mob!=undefined && mob!=""){
if(mobile.indexOf(mob)==-1)
mobile.push(mob);
}
});
promises.push(childRef);
}
}
});
promises.push(parentRef);
}
Promise.all(promises).then(function(results)
{ callAjax({EmailColl:emails,MobColl:mobile,Subject:sub,Message:message});
});

How to check whether specific items inside an array have a value? Javascript

I have a function which gets values from elements:
function getTransactionValues() {
var o = {};
o.reservations = [];
$('#custom-headers option:selected').each(function (i, selected) {
o.reservations[i] = $(selected).val();
});
o.amount = $('input[name=amount-price]').val();
o.currency_value = $('input[name=currency-value]').val();
o.currency_name = $('.currency_appendto option:selected').html();
o.actual_amount = $('input[name=actual-amount]').val();
o.actual_remaining = $('input[name=actual-remaining]').val();
o.funds_arrival_date = $('input[name=funds-arrival]').val();
o.paid_to = $('.paidto option:selected').html();
o.checkbox = $('.multi-transaction:checked').map(function () {
return this.value
}).get();
return o;
}
Now i want to check whether amount, actual_amount and funds_arrival_date are filled. if they are i will release the disabled class from a button. i've tried
var check_review = function () {
var a = getTransactionValues();
var options = [a.amount, a.actual_amount, a.funds_arrival_date];
for(i = 0; i < options.length; i++) {
if(options[i].length > 0) {
$('a[name=review_button]').removeClass('disabled');
}
else{
//this array is empty
alert('There is a problem!');
}
}
}
$('.test').click(function() {
check_review();
});
But it doesn't seems to be working..

Remove disabled attribute using JQuery?
Can you please look at above link, I think we should use $('.inputDisabled').prop("disabled", false);

Even if a single array element will be non empty then your code will remove the class disabled from the a. To make sure that all the elements of array are non empty and then only you want to remove the class then the way is:
for(i = 0; i < options.length; i++) {
if(options[i].length > 0) {
$('a[name=review_button]').removeClass('disabled');
}
else{
$('a[name=review_button]').addClass('disabled');
}
}
Or the other way is
var check = true;
for(i = 0; i < options.length; i++) {
if(options[i].length == 0) {
check = false;
}
}
if(check ) $('a[name=review_button]').removeClass('disabled');

Try using Array.prototype.every()
if (options.every(Boolean)) {
$("a[name=review_button]").removeClass("disabled");
} else {
// do other stuff
}

Binding event listeners multiple times in JavaScript

I'm trying to get the directory list, level by level, using JavaScript.
I have this paths array as input.
var _paths = [];
_paths.push("meta1/meta2/test/home/myself/hi.jpg");
_paths.push("meta1/meta2/test/home/myself/hi1.jpg");
_paths.push("meta1/meta2/test/home/myself/hi2.jpg");
_paths.push("meta1/meta2/test/work/she/100.jpg");
_paths.push("meta1/meta2/test/work/she/110.jpg");
_paths.push("meta1/meta2/test/work/she/120.jpg");
_paths.push("meta1/meta2/test/work/hard/soft/she/120.jpg");
_paths.push("meta1/meta2/test/work/hard/soft/she/121.jpg");
_paths.push("meta1/meta2/test/work/she/220.jpg");
and I want to have a "test" as output, which will be clickable. After click "test", it should be replaced by "home" and "work". After click on "home" - "myself", on "work" - "hard" and "she".
I wrote this:
CodepenCode
and it works only once, only when clicking on "test".

Simply rebind the listeners after the directories have been drawn. You bind them only once, thus they work only once.
Wrap the binding function into a named function:
function bindListeners(){
$('.sub').click(function() {
word = $(this).text();
filteredArr = findString(_paths, word);
drawList(filteredArr, word);
});
}
And call it at the end of drawList:
var drawList = function (paths, word) {
var folders = getFolders(paths, word);
if (folders.length > 0) {
$('.canvas').html('');
for (i = 0; i < folders.length; i++) {
$('.canvas').append("<div class='sub'>" + folders[i] + "</div><br />");
}
}
bindListeners();
}
Demo.

If anyone is curious about building out the data structure:
(function iteratePaths() {
var dirs = [];
for(var i = 0; i < _paths.length; i++) {
buildDirectories(dirs, _paths[i].split('/'));
}
})();
function findDir(dir, obj) {
for(var i = 0; i < dir.length; i++) {
if(dir[i].name === obj.name) {
return dir[i];
}
}
return undefined;
}
function buildDirectories(dir, subs) {
if(subs.length === 0) return;
var obj = {name: subs.shift(), dirs: []};
var existingDir = findDir(dir, obj);
if(!existingDir) {
dir.push(obj);
}
buildDirectories((existingDir || obj).dirs, subs);
}