# Comparing serial Arduino inputs with Strings in if-statements don´t work
**URL:** https://discourse.processing.org/t/comparing-serial-arduino-inputs-with-strings-in-if-statements-don-t-work/30791
**Category:** Electronics (Arduino, etc.)
**Created:** [June 19, 2021, 8:26am UTC](https://discourse.processing.org/t/comparing-serial-arduino-inputs-with-strings-in-if-statements-don-t-work/30791 "2021-06-19T08:26:09Z")
**Posts on this page:** 5
**Page:** 1
### Author:  [@Simon44](https://discourse.processing.org/u/Simon44)
#### Post date: [June 19, 2021, 8:26am UTC](https://discourse.processing.org/t/comparing-serial-arduino-inputs-with-strings-in-if-statements-don-t-work/30791/1 "2021-06-19T08:26:09Z")
Hello Community,
I´m working on my first Arduino + Processing project. The Arduino microcontroller is built as an “roll the dice” game. When I push a button on the board random numbers between 1-6 are rolled and displayed on an LED-screen. The Arduino sketch also send the rolled numbers to Processing, where they should be shown as dots on a virtual dice.
Sending the rolled numbers to Processing works fine, but at the moment I have trouble with the if-loops, which should compare the sended numbers with the statements and draw the dots .
The numbers are sended as Strings and saved to the global variable _portStream_. In the draw() loop is checked, if Strings are sended (_portStream != null_). Is that the case, the sended numbers in format String are saved in the local String variable _wuerfel_. The next if-loops should draw the dots, when the value of the String _wuerfel_ is equal to the statements “1”, “2” …
But the dots were never drawn, so there must be an error in my code or a difference between the sended numbers from the Arduino and the Statements in the if-loops. For troubleshooting the value of wuerfel is also printed in the console, but there the values looks fine. I also created the sketch with integer instead of strings, but there was the same problem, the console output looked good, but the if-loops for drawing the dots doesn´t work. I also tried to attache “\n” to the if-Statements, in case of that they are a part of the Strings from Arduino and hidden in the console.
Does anyone have a hint for the solution of the failing if-loops?
That is my code:
```auto
import processing.serial.*;
Serial myPort;
String portStream;
int diceSize = 120;
void setup() {
String portName = Serial.list()[1];
myPort = new Serial(this, portName, 9600);
myPort.bufferUntil('\n');
size(500, 500);
background(100,255,150);
}
void draw() {
if(portStream != null) {
String wuerfel = portStream;
println(wuerfel);
//Würfel
noStroke();
fill(#FFF3D6);
rectMode(CENTER);
rect(width/2, height/2, diceSize, diceSize, diceSize/5);
//Augen
fill(50);
if (wuerfel.equals("1") == true || wuerfel.equals("3") == true || wuerfel.equals("5")== true ) {
ellipse(width/2, height/2, diceSize/5, diceSize/5);
}
if (wuerfel.equals("2") == true || wuerfel.equals("3") == true || wuerfel.equals("4") == true
|| wuerfel.equals("5") == true || wuerfel.equals("6") == true ) {
ellipse(width/2 - diceSize/4, height/2 - diceSize/4, diceSize/5, diceSize/5);
ellipse(width/2 + diceSize/4, height/2 + diceSize/4, diceSize/5, diceSize/5);
}
if (wuerfel.equals("4") == true || wuerfel.equals("5") == true || wuerfel.equals("6") == true ) {
ellipse(width/2 - diceSize/4, height/2 + diceSize/4, diceSize/5, diceSize/5);
ellipse(width/2 + diceSize/4, height/2 - diceSize/4, diceSize/5, diceSize/5);
}
if (wuerfel.equals("6") == true ) {
ellipse(width/2, height/2 - diceSize/4, diceSize/5, diceSize/5);
ellipse(width/2, height/2 + diceSize/4, diceSize/5, diceSize/5);
}
delay(50);
}
}
void serialEvent(Serial myPort) {
portStream = myPort.readString();
}
```
---
### Author:  [@Chrisir](https://discourse.processing.org/u/Chrisir)
#### Post date: [June 19, 2021, 8:57am UTC](https://discourse.processing.org/t/comparing-serial-arduino-inputs-with-strings-in-if-statements-don-t-work/30791/2 "2021-06-19T08:57:51Z")
Yeah…
Maybe use trim on the incoming data…
See reference
---
### Author:  [@Simon44](https://discourse.processing.org/u/Simon44)
#### Post date: [June 19, 2021, 9:47am UTC](https://discourse.processing.org/t/comparing-serial-arduino-inputs-with-strings-in-if-statements-don-t-work/30791/3 "2021-06-19T09:47:23Z")
Thank you so much for the hint, now the programm works as expected.
I think this is missing experience but, I`ll get better with every solved problem
---
### Author:  [@glv](https://discourse.processing.org/u/glv)
#### Post date: [June 19, 2021, 10:55am UTC](https://discourse.processing.org/t/comparing-serial-arduino-inputs-with-strings-in-if-statements-don-t-work/30791/4 "2021-06-19T10:55:49Z")
Hello @Simon44,
Here is a topic that may be of interest to you:
_[Need assistance reading sequential inputs from arduino serial](https://discourse.processing.org/t/need-assistance-reading-sequential-inputs-from-arduino-serial/20368)_
You will find that there are many topics on this.
Serial communication can be a challenge at first but once you master it the _world is your oyster_… at least your code will be.
`:)`
---
### Author:  [@RichardDL](https://discourse.processing.org/u/RichardDL)
#### Post date: [June 21, 2021, 11:21am UTC](https://discourse.processing.org/t/comparing-serial-arduino-inputs-with-strings-in-if-statements-don-t-work/30791/5 "2021-06-21T11:21:45Z")
You don’t need ‘== true’ everywhere. The .equals returns a boolean, and you need a boolean expression for ‘if ()’
```auto
```