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Identical function leads to different outcomes in different languages

I wrote a function in javascript that is supposed to return the lowest prime number larger than x. Instead it get's caught in indefinite recursion.
function next_prime(x) {
if (x <= 1) {
return 2;
}
y = 2;
z = x + 1;
while(true) {
if (z % y == 0) {
z++;
y = 2;
continue;
}
if(y * y > z) {
return z;
}
y = next_prime(y);
}
}
I didn't understand what was wrong, so I implemented the same function in python, where it worked just fine.
def next_prime(x):
if x <= 1:
return 2
y = 2
z = x + 1
while True:
if z % y == 0:
z += 1
y = 2
continue
if y * y > z:
return z
y = next_prime(y)
I looked over both functions and I'm sure that they are identical, yet in python it works and in javascript it doesn't.
Allthough appreciated, I'm not necessarily looking for help with this specific problem, I'm more so interested in what is actually going on here.

I think the problem is that you are not declaring your variables correctly. In JavaScript, you have to use the keywords let and const - which stand for reassignable and not reassignable variables - when declaring a new variable. When using let in lines five and six, the function works just fine.

You should use strict mode to avoid this common mistake of javascript beginners.
your actual js code with 'use strict'; is rejected :
'use strict';
console.log( next_prime(7) ) // never run on strict mode, otherwise make an infinite loop
function next_prime(x) {
if (x <= 1) {
return 2;
}
y = 2;
z = x + 1;
while(true) {
if (z % y == 0) {
z++;
y = 2;
continue;
}
if(y * y > z) {
return z;
}
y = next_prime(y);
}
}
same code in correct javascript syntax :
'use strict';
console.log( next_prime(7) ) // -> 11
function next_prime(x)
{
if (x <= 1) return 2
;
let y = 2, z = x + 1 // declare y and z as locale
;
while(true)
{
if (z % y == 0)
{
z++;
y = 2;
continue;
}
if (y**2 > z) return z
;
y = next_prime(y);
}
}
explanation : your code is recursive, inside call will change y and z value on parent callers and make an infinite loop

my function does not fill any cases in my array in javascript

I'm trying here to solve a 4x4 skyscraper (link skyscraper game)
But the problem is that my function place insert 0 number in tab and I don't understand why console log Also I want to specify that I get 0 error: see below why console log: view code
Now when I place myself a number for example here 9, it works, in the sense that it fills the cells of the table. But here I get an error on the declaration of x, why?
console log console log: view code
I won't post all the code for the sake of readability so here is the main function place:
function place(tab, consign, pos)
{
var x = Math.floor(pos / 4);
var y = pos % 4;
if (tab[x][y] != 0)
place(tab, consign, pos + 1);
else
{
for (var index = 1; index <= 4; index++)
{
tab[x][y] = 9;
console.log(tab);
if (colnline_has_no_double(tab, x, y, index))
{
if (x % 4 == 3)
{
if (check_top_range(tab, consign, x) && check_bottom_range(tab, consign, x))
place(tab, consign, pos + 1);
}
if (y % 4 == 3)
{
if (check_left_range(tab, consign, x) && check_right_range(tab, consign, x))
place(tab, consign, pos + 1);
}
place(tab, consign, pos + 1);
}
else
tab[x][y] = 0;
if (is_filled_good(tab, consign))
{
set_data_in_input(tab);
return ;
}
index++;
}
tab[x][y] = 0;
}
}

My code gets into an infinite loop when setting up in p5

I am having real trouble finding where my loop is. I run the code and it hangs. I am trying to make a circuits game where there are circuits for the user to connect. But I am getting stuck at square one even setting up the map to make sure it is solvable. There is an infinite loop but I can't find it I looked and looked... here is the code.`
//maxLength of circut board is the board
let theHighestMaxLength = 10;
let board;
let gridX = 10;
let gridY = 10;
let perX = 10;
let perY = 10;
//s is here so we don't have to pass it everywhere the square we are looking at in functions
let s=null;
//length and usedsquares and begin are here to be used across functions
let length=0;
let usedSquares=0;
let begin=null;
class Asquare {
constructor(x, y) {
this.x = x;
this.y = y;
this.isCircut = false;
this.isWire = false;
this.OtherCircut = null;
this.Left = null;
this.Right = null;
this.Top = null;
this.Bottom = null;
this.otherCircut = null;
this.isBlank = false;
}
drawSelf() {
if (this.isCircut) {
rectMode(CENTER)
var xx = max(this.otherCircut.x, this.x);
var yy = max(this.otherCircut.y, this.y);
fill(color(xx * 25, yy * 25, 0));
square((this.x + 0.5) * perX, (this.y + 0.5) * perY, perX);
}
else if (this.isWire) {
fill(color(this.otherCircut.x * 20, this.otherCircut.y * 20, 0));
circle((this.x + 0.5) * perX, (this.y + 0.5) * perY, perX);
}
else if (this.isBlank) {
fill(color(0, 204, 0))
circle((this.x + 0.5) * perX, (this.y + 0.5) * perY, perX);
}
}
}
function handleWireMove(){
s.isWire = true;
//remember the starting circut
s.otherCircut = begin;
informAll(s);
//the length is used
length++;
}
function informAll() {
//tell all the other squares of s
if (s.x - 1 >= 0) {
board[s.x - 1][s.y].Right = s;
}
if (s.x + 1 < gridX) {
board[s.x + 1][s.y].Left = s;
}
if (s.y - 1 >= 0) {
board[s.x][s.y - 1].Bottom = s;
}
if (s.y + 1 < gridY) {
board[s.x][s.y + 1].Top = s;
}
//the used squares is now higher
usedSquares++;
}
function setup() {
createCanvas(gridX * perX, gridY * perY);
noLoop();
//fill the board with squares
board = new Array(gridX).fill(0).map(() => new Array(gridY).fill(0));
for (var x = 0; x < gridX; x++) {
for (var y = 0; y < gridY; y++) {
board[x][y] = new Asquare(x, y);
}
}
//the number of squares in the grid used
usedSquares = 0;
//till the board is full
while (usedSquares < gridX * gridY) {
//get a random x y
var rx = floor(random(gridX));
var ry = floor(random(gridY));
//create an s and begin var s for every nw square and begin for the first
s = board[rx][ry];
//if this square is already in use
if(s.isBlank||s.isCircut||s.isWire){continue;}
//begin at this square
begin = s;
//if there is some way to go
if (s.Left == null || s.Right == null || s.Top == null || s.Bottom == null) {
// get a random length to try and reach
var maxLength = floor(random(1, theHighestMaxLength))
//the starting length
length = 0;
begin.isCircut = true;
//inform all the surounding squares and increase the number of used
informAll();
//while the length isn't full
while (length <= maxLength) {
//add an option count for left right top botoom
var numOption = s.Left == null ? 1 : 0;
numOption = s.Right == null ? numOption + 1 : numOption;
numOption = s.Top == null ? numOption + 1 : numOption;
numOption = s.Bottom == null ? numOption + 1 : numOption;
//if there are no toptions to move we must stop here ot if the maxLength is reached
if (numOption == 0 || length == maxLength) {
//this is a circut the beigin circut is begin the begin other circut is this final one
s.isCircut = true;
s.isWire = false;
s.otherCicut = begin;
begin.otherCircut = s;
//make sure the loop ends
length=9999;
break;
}
//pick a random direction number
var randomChoiseNumber = floor(random(numOption));
//if left is an option
if (s.Left == null) {
//if r is already 0 that means we picked left
if (randomChoiseNumber == 0) {
//while left is an option and the maxlength isn't hit and left isn't off the map
while (s.Left == null && length < maxLength && s.x - 1 >= 0) {
//set s to the left
s = board[s.x - 1][s.y];
//handleWireMove the move
handleWireMove()
}
//continue we used the direction
continue;
} else {
//we passed an option reduce the number
randomChoiseNumber--;
}
}
//if right is an option
if (s.Right == null) {
//if this is the zero choice
if (randomChoiseNumber == 0) {
//if right is not off the map and an option while the length is not hit
while (s.Right == null && length < maxLength && s.x + 1 < gridX) {
//set s to right
s = board[s.x + 1][s.y];
//handleWireMove the move
handleWireMove();
}
continue;
} else {
//reduce the number as we passed an option
randomChoiseNumber--;
}
}
//if top is an option
if (s.Top == null) {
//if this is the zero option
if (randomChoiseNumber == 0) {
//while top is a choise and the length is not reached and top is not off the map
while (s.Top == null && length < maxLength && s.y - 1 >= 0) {
//move to the top
s = board[s.x][s.y - 1];
//handleWireMove the move
handleWireMove();
}
//continue the direction is used up
continue;
} else {
//we passed a number reduce the choise number
randomChoiseNumber--;
}
}
//if bottom is an option
if (s.Bottom == null) {
//if this is the zero option
if (randomChoiseNumber == 0) {
//while bottom is a choise and the length is not reached and it is not off the map
while (s.Bottom == null && length < maxLength && s.y + 1 < gridY) {
//go to the bottom
s = board[s.x][s.y + 1];
//handleWireMove the move
handleWireMove();
}
}
}
}
}
else {
//if there was no way to go the square is blank tell the others and increace usedSquares
s.isBlank = true;
informAll();
}
}
}
function drawAll() {
board.forEach(a => a.forEach(b => b.drawSelf()));
}
function draw() {
background(gridX * perX);
drawAll();
}
The problem is in the setup function but I can't find it. Please help

The problem is that you compute the number of available numOption only based on whether the randomly selected grid square has unconnected slots (Left, Top, Right, or Bottom) without considering whether the value of s.x and s.y make it possible to select one of those directions). As a result your inner loop repeats infinitely because it never calls handleWireMove() and thus never increases length.
The code below is modified with some extra logging and it becomes obvious where the infinite loop is (it eventually prints 'we failed to make a choice. that is not good' forever):
//the number of squares in the grid used
usedSquares = 0;
//till the board is full
while (usedSquares < gridX * gridY) {
console.log(usedSquares);
//get a random x y
var rx = floor(random(gridX));
var ry = floor(random(gridY));
//create an s and begin var s for every nw square and begin for the first
s = board[rx][ry];
//if this square is already in use
if (s.isBlank || s.isCircut || s.isWire) {
continue;
}
//begin at this square
begin = s;
//if there is some way to go
if (
s.Left == null ||
s.Right == null ||
s.Top == null ||
s.Bottom == null
) {
// get a random length to try and reach
var maxLength = floor(random(1, theHighestMaxLength));
//the starting length
length = 0;
begin.isCircut = true;
//inform all the surounding squares and increase the number of used
informAll();
//while the length isn't full
console.log('beggining inner loop');
while (length <= maxLength) {
//add an option count for left right top botoom
var numOption = s.Left == null ? 1 : 0;
numOption = s.Right == null ? numOption + 1 : numOption;
numOption = s.Top == null ? numOption + 1 : numOption;
numOption = s.Bottom == null ? numOption + 1 : numOption;
//if there are no toptions to move we must stop here ot if the maxLength is reached
if (numOption == 0 || length == maxLength) {
//this is a circut the beigin circut is begin the begin other circut is this final one
s.isCircut = true;
s.isWire = false;
s.otherCicut = begin;
begin.otherCircut = s;
//make sure the loop ends
console.log('no options, abort');
length = 9999;
break;
}
//pick a random direction number
var randomChoiseNumber = floor(random(numOption));
//if left is an option
if (s.Left == null) {
//if r is already 0 that means we picked left
if (randomChoiseNumber == 0) {
//while left is an option and the maxlength isn't hit and left isn't off the map
while (s.Left == null && length < maxLength && s.x - 1 >= 0) {
//set s to the left
s = board[s.x - 1][s.y];
//handleWireMove the move
handleWireMove();
}
//continue we used the direction
continue;
} else {
//we passed an option reduce the number
randomChoiseNumber--;
}
}
//if right is an option
if (s.Right == null) {
//if this is the zero choice
if (randomChoiseNumber == 0) {
//if right is not off the map and an option while the length is not hit
while (s.Right == null && length < maxLength && s.x + 1 < gridX) {
//set s to right
s = board[s.x + 1][s.y];
//handleWireMove the move
handleWireMove();
}
continue;
} else {
//reduce the number as we passed an option
randomChoiseNumber--;
}
}
//if top is an option
if (s.Top == null) {
//if this is the zero option
if (randomChoiseNumber == 0) {
//while top is a choise and the length is not reached and top is not off the map
while (s.Top == null && length < maxLength && s.y - 1 >= 0) {
//move to the top
s = board[s.x][s.y - 1];
//handleWireMove the move
handleWireMove();
}
//continue the direction is used up
continue;
} else {
//we passed a number reduce the choise number
randomChoiseNumber--;
}
}
//if bottom is an option
if (s.Bottom == null) {
//if this is the zero option
if (randomChoiseNumber == 0) {
//while bottom is a choise and the length is not reached and it is not off the map
while (s.Bottom == null && length < maxLength && s.y + 1 < gridY) {
//go to the bottom
s = board[s.x][s.y + 1];
//handleWireMove the move
handleWireMove();
}
}
}
console.log('we failed to make a choice. that is not good');
}
console.log('exited inner loop');
} else {
//if there was no way to go the square is blank tell the others and increace usedSquares
s.isBlank = true;
informAll();
}
}
Here is a working version that correctly checks not only if there is an opening to the Left/Top/Right/Bottom, but also if that direction is possible (not off the edge of the grid):
//maxLength of circut board is the board
let theHighestMaxLength = 10;
let board;
let gridX = 10;
let gridY = 10;
let perX = 10;
let perY = 10;
//s is here so we don't have to pass it everywhere the square we are looking at in functions
let s = null;
//length and usedsquares and begin are here to be used across functions
let length = 0;
let usedSquares = 0;
let begin = null;
class Asquare {
constructor(x, y) {
this.x = x;
this.y = y;
this.isCircut = false;
this.isWire = false;
this.OtherCircut = null;
this.Left = null;
this.Right = null;
this.Top = null;
this.Bottom = null;
this.otherCircut = null;
this.isBlank = false;
}
drawSelf() {
if (this.isCircut) {
rectMode(CENTER);
var xx = max(this.otherCircut.x, this.x);
var yy = max(this.otherCircut.y, this.y);
fill(color(xx * 25, yy * 25, 0));
square((this.x + 0.5) * perX, (this.y + 0.5) * perY, perX);
} else if (this.isWire) {
fill(color(this.otherCircut.x * 20, this.otherCircut.y * 20, 0));
circle((this.x + 0.5) * perX, (this.y + 0.5) * perY, perX);
} else if (this.isBlank) {
fill(color(0, 204, 0));
circle((this.x + 0.5) * perX, (this.y + 0.5) * perY, perX);
}
}
}
function handleWireMove() {
s.isWire = true;
//remember the starting circut
s.otherCircut = begin;
informAll(s);
//the length is used
length++;
}
function informAll() {
//tell all the other squares of s
if (s.x - 1 >= 0) {
board[s.x - 1][s.y].Right = s;
}
if (s.x + 1 < gridX) {
board[s.x + 1][s.y].Left = s;
}
if (s.y - 1 >= 0) {
board[s.x][s.y - 1].Bottom = s;
}
if (s.y + 1 < gridY) {
board[s.x][s.y + 1].Top = s;
}
//the used squares is now higher
usedSquares++;
}
function setup() {
createCanvas(gridX * perX, gridY * perY);
noLoop();
//fill the board with squares
board = new Array(gridX).fill(0).map(() => new Array(gridY).fill(0));
for (var x = 0; x < gridX; x++) {
for (var y = 0; y < gridY; y++) {
board[x][y] = new Asquare(x, y);
}
}
//the number of squares in the grid used
usedSquares = 0;
//till the board is full
while (usedSquares < gridX * gridY) {
console.log(usedSquares);
//get a random x y
var rx = floor(random(gridX));
var ry = floor(random(gridY));
//create an s and begin var s for every nw square and begin for the first
s = board[rx][ry];
//if this square is already in use
if (s.isBlank || s.isCircut || s.isWire) {
continue;
}
//begin at this square
begin = s;
//if there is some way to go
if (
s.Left == null ||
s.Right == null ||
s.Top == null ||
s.Bottom == null
) {
// get a random length to try and reach
var maxLength = floor(random(1, theHighestMaxLength));
//the starting length
length = 0;
begin.isCircut = true;
//inform all the surounding squares and increase the number of used
informAll();
//while the length isn't full
console.log('beggining inner loop');
while (length <= maxLength) {
//add an option count for left right top botoom
var numOption = s.Left == null && s.x - 1 >= 0 ? 1 : 0;
numOption = s.Right == null && s.x + 1 < gridX ? numOption + 1 : numOption;
numOption = s.Top == null && s.y - 1 >= 0 ? numOption + 1 : numOption;
numOption = s.Bottom == null && s.y + 1 < gridY ? numOption + 1 : numOption;
//if there are no toptions to move we must stop here ot if the maxLength is reached
if (numOption == 0 || length == maxLength) {
//this is a circut the beigin circut is begin the begin other circut is this final one
s.isCircut = true;
s.isWire = false;
s.otherCicut = begin;
begin.otherCircut = s;
//make sure the loop ends
console.log('no options, abort');
length = 9999;
break;
}
//pick a random direction number
var randomChoiseNumber = floor(random(numOption));
//if left is an option
if (s.Left == null && s.x - 1 >= 0) {
//if r is already 0 that means we picked left
if (randomChoiseNumber == 0) {
//while left is an option and the maxlength isn't hit and left isn't off the map
while (s.Left == null && length < maxLength && s.x - 1 >= 0) {
//set s to the left
s = board[s.x - 1][s.y];
//handleWireMove the move
handleWireMove();
}
//continue we used the direction
continue;
} else {
//we passed an option reduce the number
randomChoiseNumber--;
}
}
//if right is an option
if (s.Right == null && s.x + 1 < gridX) {
//if this is the zero choice
if (randomChoiseNumber == 0) {
//if right is not off the map and an option while the length is not hit
while (s.Right == null && length < maxLength && s.x + 1 < gridX) {
//set s to right
s = board[s.x + 1][s.y];
//handleWireMove the move
handleWireMove();
}
continue;
} else {
//reduce the number as we passed an option
randomChoiseNumber--;
}
}
//if top is an option
if (s.Top == null && s.y - 1 >= 0) {
//if this is the zero option
if (randomChoiseNumber == 0) {
//while top is a choise and the length is not reached and top is not off the map
while (s.Top == null && length < maxLength && s.y - 1 >= 0) {
//move to the top
s = board[s.x][s.y - 1];
//handleWireMove the move
handleWireMove();
}
//continue the direction is used up
continue;
} else {
//we passed a number reduce the choise number
randomChoiseNumber--;
}
}
//if bottom is an option
if (s.Bottom == null && s.y + 1 < gridY) {
//if this is the zero option
if (randomChoiseNumber == 0) {
//while bottom is a choise and the length is not reached and it is not off the map
while (s.Bottom == null && length < maxLength && s.y + 1 < gridY) {
//go to the bottom
s = board[s.x][s.y + 1];
//handleWireMove the move
handleWireMove();
}
}
}
console.log('we failed to make a choice. that is not good');
}
console.log('exited inner loop');
} else {
//if there was no way to go the square is blank tell the others and increace usedSquares
s.isBlank = true;
informAll();
}
}
}
function drawAll() {
board.forEach((a) => a.forEach((b) => b.drawSelf()));
}
function draw() {
background(gridX * perX);
drawAll();
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/p5.js/1.4.0/p5.js"></script>
One closing though: this bug is a symptom of this code being horribly complicated and violating fundamental principles of good design such as not having shared global state that is updated as a side effect of function calls.

On the fabricjs how can you determine if an object already exists at certain coordinates?

I have been working with fabricjs for the last few weeks and I cannot find a solution for an issue I am having.
I have an object and I would like to programmatically determine if the area around it is "empty" (there are no objects ), so if I would add an object there they would not intersect.
I have been playing around with canvas.findTarget and different "virtual" objects but I cannot get anything to work.
This is a solution I found:
var targetPoint = new fabric.Point(target.left + offset + 1, target.top + 1);
if (obj.containsPoint(targetPoint)) {
objectOnRight = obj;
}
Best regards,
Alex

This should get you fairly close (some code I've used, in the past, to display a context menu):
fabric.util.addListener(document.getElementsByClassName('upper-canvas')[0], 'contextmenu', function (env) {
var x = env.offsetX;
var y = env.offsetY;
var itemIndex = -1;
$.each(canvas.getObjects(), function (i, e) {
// e.left and e.top are the middle of the object use some "math" to find the outer edges
if (e.selectable && e.id != 'canvasNumbers') {
var d = e.width * e.scaleX / 2;
var h = e.height * e.scaleY / 2;
if (x >= (e.left - d) && x <= (e.left + d)) {
if (y >= (e.top - h) && y <= (e.top + h)) {
itemIndex = i;
}
}
}
});
if (itemIndex > -1) {
canvas.setActiveObject(canvas.getObjects()[itemIndex]);
canvasSelectedItem = canvas.getObjects()[itemIndex];
$('.contextmenu').css({
top: env.pageY + 'px',
left: env.pageX + 'px'
}).show();
}
env.preventDefault();
return false; //stops the event propigation
});
Let me know if you have any further questions. Happy to help more!

I have an idea of using two events here to catch when mouse is over a given object and when out:
myobject[i].on('mouseover', () => {
console.log("mouse over"+i)
});
myobject[i].on('mouseout', () => {
console.log("mouse out"+i)
});

Highcharts bar chart datalabels overlap

I'm using highcharts bar chart.The Series is dynamically loaded so there can be sometime only one value and some times 10 values.I can't give a set width.I m having an issue where The datalabels on the top of bar chart is overlapping with each other when there are lot of values. After doing research on internet the closest thing I could find for this issue is on stackflow which is for two or more series
Overlap datalabels line chart highcharts
Is there any way we can detect the overlap for a single series and adjust the datalabel so it is not overlapping with each other.
Thanks for any kind of help

In general this solution is not supported, but you adapt this workaround
function StaggerDataLabels(series) {
sc = series.length;
if (sc < 2) return;
for (s = 1; s < sc; s++) {
var s1 = series[s - 1].points,
s2 = series[s].points,
l = s1.length,
diff, h;
for (i = 0; i < l; i++) {
if (s1[i].dataLabel && s2[i].dataLabel) {
diff = s1[i].dataLabel.y - s2[i].dataLabel.y;
h = s1[i].dataLabel.height + 2;
if (isLabelOnLabel(s1[i].dataLabel, s2[i].dataLabel)) {
if (diff < 0) s1[i].dataLabel.translate(s1[i].dataLabel.translateX, s1[i].dataLabel.translateY - (h + diff));
else s2[i].dataLabel.translate(s2[i].dataLabel.translateX, s2[i].dataLabel.translateY - (h - diff));
}
}
}
}
}
//compares two datalabels and returns true if they overlap
function isLabelOnLabel(a, b) {
var al = a.x - (a.width / 2);
var ar = a.x + (a.width / 2);
var bl = b.x - (b.width / 2);
var br = b.x + (b.width / 2);
var at = a.y;
var ab = a.y + a.height;
var bt = b.y;
var bb = b.y + b.height;
if (bl > ar || br < al) {
return false;
} //overlap not possible
if (bt > ab || bb < at) {
return false;
} //overlap not possible
if (bl > al && bl < ar) {
return true;
}
if (br > al && br < ar) {
return true;
}
if (bt > at && bt < ab) {
return true;
}
if (bb > at && bb < ab) {
return true;
}
return false;
}
http://jsfiddle.net/menXU/6/.