NaN error

kairama15

I have been struggling with one of my variables reading NaN and 'infinity'. I have been struggling with it for 2 hours. If I copy and paste the formula for "radius" in my program into wolframalpha, I get a real result. Anyone have any ideas?

void setup() { size(800, 600); background(255); }

float px = 425; float py = 350; float radius=5*atan(5/(1000+800-425))/atan(5/(400+1000));

void star() { fill(#F6FF00); ellipse(400, 300,10,10); }

void planet() {

print(radius); radius = 5*atan(5/(1000+800-px))/atan(5/(400+1000)); ellipse(px,py,5,5); }

void draw() { star(); planet(); }

The variable 'radius' is the problem. It prints the variable as 'NaN' once and then 'Infinity' as it loops through the program.

I took out 90% of the program so it fits in the post. The calculation is superfluous for the written portion on this post but it is important for the rest of the program.

GoToLoop

In Java the division operator / removes the fractional part from the result if both operands are of whole type. L-)

GoToLoop

https://forum.Processing.org/two/discussion/15473/readme-how-to-format-code-and-text

float radius=5*atan(5./(1000+800-425))/atan(5./(400+1000));

kairama15

I apologizing for not formatting the text better.

I replaced the 5/(1000+... with 5./(1000+... in the program and it works great with no errors. Thank you for your time.

I am struggling why a programming language would drop the fractional/decimal part of a variable just because. Should I just put a decimal place after every integer I use to avoid this? And what do you mean whole type?

Thanks!

GoToLoop

• Java got 8 primitive datatypes identified by 8 keywords.
• Apart from boolean, the other 7 are numerical.
• And outta those 7, 2 are fractional: float & double.
• All the rest is whole (integer) types: char, byte, short, int, long.

GoToLoop

Should I just put a decimal place after every integer I use to avoid this?

As I've mentioned it's enough for at least 1 of the operands (the 2 expression sides of the operator) to be fractional. For example: for 1/2 we can 1./2, 1/2. or 1./2.. B-)

GoToLoop

... why a programming language would drop the fractional/decimal part of a variable just because.

Consistence & performance. Integer operations are faster than floating 1s after all.
If we declare that some variable is of type int and we try to assign 4/3 to it, the result would need to be coerced from float or double back to int.
Java automatically coerces upwards. But refrains for backwards conversions. 8-|

koogs

Should I just put a decimal place after every integer I use to avoid this?

I would always add .0 rather than just a . because the latter just looks like punctuation and is easily overlooked