Sieve of eratosthenes processing problem not drawing rectables in Processing - processing

I am trying to create the Sieve of Eratosthenes problem where I print out a grid from 2 to 100 and then cover all non-prime numbers with a rectangle. I can only get it to check one divisor between 2 and 10. I cant get it to loop through all divisors. my current version doesn't print any rectangles what so ever but it feels like it should be because reading it it looks like if variable a is less than 10 check if the number in that location is divisible by a. if it is print a rectangle there. once it checks all of those it add 1 to a. Where am I going wrong here?
int a=2;
void setup()
{
size(600, 600);
rectMode(CORNER);
textSize(17);
background(0);
for (int x = 0; x < 10; x++)
{
for (int y =0; y<11; y++)
{
if ((x)+((y-1)*10)+1>1)
{
fill(255);
text((x)+((y-1)*10)+1, x*50+30, y*50);
}
}
}
}
void draw()
{
for (int x = 0; x < 10; x++)
{
for (int y =0; y<10; y++)
{
while (a<10)
{
if ((x)+((y-1)*10)+1%a==0)
{
fill(50, 50, 200);
rect((x)*50+30, (y)*50+30, 30, 30);
}
a++;
}
}
}
}

You have several problems in Your solution.
((x)+((y-1)*10)+1>1) formula is overcomplex for this problem,
void draw() is a loop, so Your 'a' variable will never go back to value 2.
Use System.out.println(); wherever You are not sure what is going on.
So, here is the cleaner concept of Your problem:
in Your case there is no need to call draw(),
set 'a' value every time before while(), not just once before setup(),
draw Your boxes just inside the same place as text()
void setup() {
size(600, 600);
background(0);
fill(255);
for (int y=0; y<10; y++) {
for (int x=1; x<=10; x++) {
System.out.println(x + ", " + y + ": " + (x+y*10));
int a=2;
textSize(26);
while (a<=Math.sqrt(x+y*10)) {
if ((x+y*10)%a == 0) {
System.out.println(a+": "+x+", " +y+": "+(x+y*10));
textSize(12);
}
a++;
}
text(x+y*10, x*50, y*50+50);
}
}
}
void draw() {
}

Related

Processing String splitting and loops to form a facade

I have tried many methods, and can't seem to grasp the idea of extracting an index from my array of strings to help me generate my desired number of building with a desired height, please help, here is my example
edit: Hi, i saw your feedback and posted my code below, hopefully it helps with the idea overall, as much as it is just creating rects, its more complicated as i need to involve arrays and string splitting along with loops. i more or less got that covered but i as i said above, i cannot extract the values from my array of string and create my facades at my own desired number and height
String buffer = " ";
String bh = "9,4,6,8,12,2";
int[] b = int(split(bh, ","));
int buildingheight = b.length;
void setup () {
size(1200, 800);
background(0);
}
void draw () {
}
void Textbox() {
textSize(30);
text(buffer, 5, height-10);
}
void keyTyped() {
if (key == BACKSPACE) {
if (buffer.length() > 0) {
buffer = buffer.substring(0, buffer.length() - 1);
}
} else if (key == ENTER) {
background(0);
stroke(0);
GenerateFacade();
println(buffer);
}
else {
buffer = buffer + key;
Textbox();
}
}
void GenerateFacade() {
fill(128);
for (int i = 0; i < b.length; i++) {
for (int j = 0; j < b.length; j++) {
if (int(b[j]) > buildingheight) {
buildingheight = int(b[j]);
}
}
rect(i*width/b.length, height - (int(b[i])*height/buildingheight), width/b.length, int(b[i])*height/buildingheight);
}
}
For the next time it would be great if you provide us with some code so we know what you tried and maybe can point you to the problem you have.
You need just the keyPressed function and some variables
int x = 0;
int buildingWidth = 50;
int buildingHeight = height / 6;
void setup(){
size(1000, 500);
background(255);
}
void draw(){
}
void keyPressed(){
if(key >= '0' && key <= '9'){
int numberPressed = key - '0' ;
fill(0);
rect(x, height - buildingHeight * numberPressed,
buildingWidth, buildingHeight * numberPressed);
x += buildingWidth;
}
}
This is my result

How can I create points, display them and store them in some sort of Array

I want to create points and then store them in an array. I'm doing this to put a linear regression through my data points afterwards. So I need to be able to cycle through all my points.
I could not find anything like that on the web for processing and as I was not really able to do it, I need your help. Here is my approach, but it doesn't seem to work:
ArrayList<dataPoint> dataPoints = new ArrayList<dataPoint>();
void setup(){
size(1000, 1000);
background(255);
}
void draw(){
for (int i = 1; i == dataPoints.size(); i++) {
// An ArrayList doesn't know what it is storing so we have to cast the object coming out
dataPoint Point = dataPoints.get(i);
Point.display();
}
}
void mousePressed() {
dataPoints.add(new dataPoint(mouseX, mouseY));
}
class dataPoint {
float x;
float y;
dataPoint(int tempX, int tempY) {
x = tempX;
y = tempY;
}
void display() {
strokeWeight(10);
stroke(255,0,0);
point(x,y);
}
}
I would like to have a program to create points and store them in an array (or something similar, that you can cycle through).
Most of your code makes sense, there are only two gotchas I could spot that may prevent you from cycling through all your points and visualising them:
your condition is will go to an array index out of bounds: try for (int i = 0; i < dataPoints.size(); i++)
remember to clear the frame, otherwise you're drawing on top of the same dots over and over again
Remember array indices start at 0 in Processing/Java (and likewise the last index will not be the size() of your array, but the 1 less, hence the < in the for condition)
Here is your code with the above tweaks:
ArrayList<dataPoint> dataPoints = new ArrayList<dataPoint>();
void setup(){
size(1000, 1000);
}
void draw(){
background(255);
for (int i = 0; i < dataPoints.size(); i++) {
// An ArrayList doesn't know what it is storing so we have to cast the object coming out
dataPoint Point = dataPoints.get(i);
Point.display();
}
}
void mousePressed() {
dataPoints.add(new dataPoint(mouseX, mouseY));
}
class dataPoint {
float x;
float y;
dataPoint(int tempX, int tempY) {
x = tempX;
y = tempY;
}
void display() {
strokeWeight(10);
stroke(255,0,0);
point(x,y);
}
}
Note that Processing has a handy PVector class (which has x,y properties) so you could do something like this:
ArrayList<PVector> dataPoints = new ArrayList<PVector>();
void setup(){
size(1000, 1000);
strokeWeight(10);
stroke(255,0,0);
noFill();
}
void draw(){
background(255);
beginShape();
for (int i = 0; i < dataPoints.size(); i++) {
PVector point = dataPoints.get(i);
vertex(point.x,point.y);
}
endShape();
}
void mousePressed() {
dataPoints.add(new PVector(mouseX, mouseY));
}
This a bit of a detail, but I recommend to following Java Naming Convention to keep the code consistent. (For example: renaming the dataPoint class to DataPoint and renaming the Point instance to point)

How to get enemy that is being hit to disappear

I'm currently working on a school project and I'm trying to make a game similar to galaga. My problem is that whenever the bullet hits the enemy, another enemy would disappear. I believe this is because of the fact that I'm using a for loop and the enemies are being deleted in sequential order. Another problem I am having is with the bullets, I do not know why it slows down and eventually disappears as the number of the enemies decreases. Any help is appreciated.
ArrayList<enemy> e = new ArrayList<enemy>();
ArrayList<bullet> b = new ArrayList<bullet>();
boolean shoot = false;
void setup() {
fullScreen();
//enemy
for (int i = 0; i<5; i++) {
e.add(new enemy(50, 50));
}
//bullet
for (int i = 0; i<5; i++) {
b.add(new bullet(mouseX, mouseY));
}
}
void draw() {
background(255);
for (int p = 0; p<e.size(); p++) {
for (int i = 0; i<b.size(); i++) {
bullet a = b.get(i);
enemy o = e.get(p);
if (a.update()) {
b.remove(i);
}
if (o.col()) {
b.remove(i);
e.remove(i);
}
}
}
//enemy
for (int i = 0; i<e.size(); i++) {
enemy a = e.get(i);
a.display();
}
}
void mouseReleased() {
shoot = true;
b.add(new bullet(mouseX, mouseY));
}
class enemy {
int x, y, w, h;
int enemyX = int(random(width));
int enemyY = int(random(200));
public enemy(int tempenemyW, int tempenemyH) {
int tempenemyX = enemyX;
int tempenemyY = enemyY;
this.x = tempenemyX;
this.y = tempenemyY;
this.w = tempenemyW;
this.h = tempenemyH;
}
void display() {
fill(255, 0, 0);
rect(this.x, this.y, this.w, this.h);
}
boolean col() {
for (int i = 0; i<b.size(); i++) {
bullet a = b.get(i);
if (a.x+a.w>this.x && a.x<this.x+this.w && a.y+a.h+a.bulletSpeed>this.y && a.y+a.bulletSpeed<this.y+this.h) {
return true;
}
}
return false;
}
}
class bullet {
int x, y, w, h;
int bulletSpeed = 10;
public bullet(int tempx, int tempy) {
int tempw = 3;
int temph = 20;
this.x = tempx;
this.y = tempy;
this.w = tempw;
this.h = temph;
}
boolean update() {
this.y -= bulletSpeed;
fill(0, 255, 0);
rect(this.x, this.y, this.w, this.h, 100, 100, 100, 100);
if (x<0 || x>width || y<0 || y>height) {
return true;
} else {
return false;
}
}
}
Your removing the enemy that lives at the index of the bullet instead of the enemy at the index of the enemy. To fix this, try changing the line
e.remove(i);
to
e.remove(p);
I also recommend that you give better variable names. The reason that this was confusing for you is because "i" and "p" aren't very descriptive or helpful. It would have been easier to spot the mistake if the middle of the draw function looked like this:
for (int enemyIndex = 0; enemyIndex<e.size(); enemyIndex++) {
for (int bulletIndex = 0; bulletIndex<b.size(); bulletIndex++) {
bullet currentBullet = b.get(bulletIndex);
enemy currentEnemy = e.get(enemyIndex);
if (a.update()) {
b.remove(bulletIndex);
}
if (currentEnemy.col()) {
b.remove(bulletIndex);
e.remove(bulletIndex); // Clearly the wrong index!
}
}
}
Then you could go further by changing the names of your lists to "bullets" and "enemies" instead of just "b" and "e" :p
Teddy's answer is half the story. The other half of the story is that you're removing items from the list as you loop over it.
Let's say you have a loop like this:
for(int index = 0; index < list.size(); index++){
if(list.get(index).contains("remove me")){
list.remove(index);
}
}
And let's say your list looks like this:
0: "keep"
1: "remove me one"
2: "remove me two"
3: "keep"
Go through the loop with this list in mind. When index is 0, it sees "keep" and doesn't do anything. Now index is 1 and it sees "remove me one" so it removes the item at index 1 and every index after that shifts down one, making the list this:
0: "keep"
1: "remove me two"
2: "keep"
But index is still 1 at the end of the loop, so it increases to 2, and the next iteration sees "keep".
In other words, we skip over "remove me two" because we never check that index when it's shifted down by one.
The solution to this problem is to either use an Iterator or to loop backwards over the list.
Shameless self-promotion: I wrote a tutorial on using ArrayLists in Processing available here. See the section on removing items from an ArrayList.

Automation of selection in Processing

I am currently using a processing sketch to work through a large number of images I have in a folder. I have set an onClick command to advance to the next image in the string. It is quite time consuming and I would like to automate the action that once the sketch is completed the sketch would repeat it's self selecting the next image from the string. The onClick command also save the image the export folder but each time saves with the same file name, I've tried to set up sequential numbering but it hasn't worked so far. Any help would be greatly appreciated.
String[] imgNames = {"1.jpg", "2.jpg", "3.jpg"};
PImage img;
int imgIndex = 0;
void nextImage() {
background(255);
frameRate(10000);
loop();
frameCount = 0;
img = loadImage(imgNames[imgIndex]);
img.loadPixels();
imgIndex += 1;
if (imgIndex >= imgNames.length) {
imgIndex = 0;
}
}
void paintStroke(float strokeLength, color strokeColor, int strokeThickness) {
float stepLength = strokeLength/4.0;
// Determines if the stroke is curved. A straight line is 0.
float tangent1 = 0;
float tangent2 = 0;
float odds = random(1.0);
if (odds < 0.7) {
tangent1 = random(-strokeLength, strokeLength);
tangent2 = random(-strokeLength, strokeLength);
}
// Draw a big stroke
noFill();
stroke(strokeColor);
strokeWeight(strokeThickness);
curve(tangent1, -stepLength*2, 0, -stepLength, 0, stepLength, tangent2, stepLength*2);
int z = 1;
// Draw stroke's details
for (int num = strokeThickness; num > 0; num --) {
float offset = random(-50, 25);
color newColor = color(red(strokeColor)+offset, green(strokeColor)+offset, blue(strokeColor)+offset, random(100, 255));
stroke(newColor);
strokeWeight((int)random(0, 3));
curve(tangent1, -stepLength*2, z-strokeThickness/2, -stepLength*random(0.9, 1.1), z-strokeThickness/2, stepLength*random(0.9, 1.1), tangent2, stepLength*2);
z += 1;
}
}
void setup() {
size(1600, 700);
nextImage();
}
void draw() {
translate(width/2, height/2);
int index = 0;
for (int y = 0; y < img.height; y+=1) {
for (int x = 0; x < img.width; x+=1) {
int odds = (int)random(20000);
if (odds < 1) {
color pixelColor = img.pixels[index];
pixelColor = color(red(pixelColor), green(pixelColor), blue(pixelColor), 100);
pushMatrix();
translate(x-img.width/2, y-img.height/2);
rotate(radians(random(-90, 90)));
// Paint by layers from rough strokes to finer details
if (frameCount < 20) {
// Big rough strokes
paintStroke(random(150, 250), pixelColor, (int)random(20, 40));
} else if (frameCount < 1000) {
// Thick strokes
paintStroke(random(75, 125), pixelColor, (int)random(8, 12));
} else if (frameCount < 1500) {
// Small strokes
paintStroke(random(20, 30), pixelColor, (int)random(1, 4));
} else if (frameCount < 10000) {
// Big dots
paintStroke(random(5, 10), pixelColor, (int)random(5, 8));
} else if (frameCount < 10000) {
// Small dots
paintStroke(random(1, 2), pixelColor, (int)random(1, 3));
}
popMatrix();
}
index += 1;
}
}
if (frameCount > 10000) {
noLoop();
}
// if(key == 's'){
// println("Saving...");
// saveFrame("screen-####.jpg");
// println("Done saving.");
// }
}
void mousePressed() {
save("001.tif");
nextImage();
}
Can't you just call the nextImage() function from inside this if statement?
if (frameCount > 10000) {
noLoop();
}
Would be:
if (frameCount > 10000) {
nextImage();
}
As for using different filenames, just use an int that you increment whenever you save the file, and use that value in the save() function. Or you could use the frameCount variable:
save("img" + frameCount + ".tif");
If you have follow-up questions, please post a MCVE instead of your whole project. Try to isolate one problem at a time in a small example program that only does that one thing. Good luck.

Processing: Numbered Image squence

I am trying to create 100 frames where the numbers 0-100 are "printed" in the center of every frame. If I try the code below I get the error "It looks like you're mixing "active" and "static" modes".
size(1440,900);
font = loadFont("Arial-Black-96.vlw");
textFont(font,96);
int x = 0;
void draw() {
background(204);
y=0;
if (x < 100) {
text(y, 10, 50);
x = x + 1;
y=y+1;
} else {
noLoop();
}
// Saves each frame as screen-0001.tif, screen-0002.tif, etc.
saveFrame();
}
You need to wrap the first 3 lines in the setup() function.
Like:
void setup(){
size(1440,900);
font = loadFont("Arial-Black-96.vlw");
textFont(font,96);
}
I answered this without running the code, there were others issues, here a version of your code:
PFont font;
int x = 0;
int size = 96;
void setup() {
size(1440, 900);
font = createFont("Arial-Black", size);
textFont(font);
}
void draw() {
background(204);
if (x <= 100) {
String number = nf(x, 2);
text(number, width/2 - textWidth(number)/2, height/2);
x++;
saveFrame();
}
else {
exit();
}
}

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