# How can I run a for loop using a function?
**URL:** https://discourse.processing.org/t/how-can-i-run-a-for-loop-using-a-function/17403
**Category:** Coding Questions
**Created:** [January 28, 2020, 10:27pm UTC](https://discourse.processing.org/t/how-can-i-run-a-for-loop-using-a-function/17403 "2020-01-28T22:27:34Z")
**Posts on this page:** 5
**Page:** 1
### Author:  [@Daniele92](https://discourse.processing.org/u/Daniele92)
#### Post date: [January 28, 2020, 10:27pm UTC](https://discourse.processing.org/t/how-can-i-run-a-for-loop-using-a-function/17403/1 "2020-01-28T22:27:34Z")
Hello to everyone. Can someone explain to me , How can I run a :
```auto
for( int i=100; i>0; i=i-10 ) {
ellipse(100,100,i,i);
}
```
Using a function?!
Thank you , i DON’t want a code but need to understand for classroom activity.
---
### Author:  [@Chrisir](https://discourse.processing.org/u/Chrisir)
#### Post date: [January 28, 2020, 10:33pm UTC](https://discourse.processing.org/t/how-can-i-run-a-for-loop-using-a-function/17403/2 "2020-01-28T22:33:19Z")
for using a function you need a full sketch with setup and draw and your new function.
For `setup()` and `draw()` see [https://www.processing.org/tutorials/overview/](https://www.processing.org/tutorials/overview/)
A function can be inserted at different levels of your sketch: You could either
- replace ellipse(100,100,i,i); with a function (named `myEllipse(float i)`) that gets i as a parameter OR
- replace your entire code (all three lines) with a function (`ellipseArt()`) without parameters.
More about functions: see [https://github.com/Kango/Processing-snippets/wiki/programming-and-functions](https://github.com/Kango/Processing-snippets/wiki/programming-and-functions)
---
### Author:  [@Daniele92](https://discourse.processing.org/u/Daniele92)
#### Post date: [January 28, 2020, 10:49pm UTC](https://discourse.processing.org/t/how-can-i-run-a-for-loop-using-a-function/17403/3 "2020-01-28T22:49:29Z")
To be honest I’m newbie ( first three months of experience)
```auto
void setup() {
size(500,300);
background(255);
for(int i=100; i>0; i=i-10) {
ellipse(100,100,i,i);
}
}
void draw() {
}
```
Should I create a function calling ABC… with int/void? I really want to improve My self. Can you pls do some Example?
---
### Author:  [@Chrisir](https://discourse.processing.org/u/Chrisir)
#### Post date: [January 28, 2020, 10:58pm UTC](https://discourse.processing.org/t/how-can-i-run-a-for-loop-using-a-function/17403/4 "2020-01-28T22:58:46Z")
```auto
void setup() {
size(500, 300);
background(0);
}
void draw() {
background(0);
for (int i=100; i>0; i=i-10) {
myEllipse(i);
}
}
void myEllipse(float i) {
ellipse(100, 100, i, i);
}
```
---
### Author:  [@Chrisir](https://discourse.processing.org/u/Chrisir)
#### Post date: [January 28, 2020, 11:01pm UTC](https://discourse.processing.org/t/how-can-i-run-a-for-loop-using-a-function/17403/5 "2020-01-28T23:01:40Z")
and welcome to the forum!
Great to have you here!