I never really did well in math at school; witch is kinda funny since i love programming!
Anyway, im making a game and i want to create a bell curve of probability.
Basically, i want some number (x) to be very common, and the further out you go to (y) the less common it becomes.
like this: http://andihammer.com/wp-content/uploads/2013/10/6a00d834525fff69e20133ecf35c3d970b-800wi.gif
The center to be very common, and the further out you go the less common it becomes.
Whats a math function i could use, thats simple enought for my 10th grade mind to understand, while suits the propose.
Its worth noting the numbers would be really small. 15 would be normal, 10 min 20 max.
Also id like 10 and 20 to have like a 30% chance, leaving 40% for the 15. There would be number in-between also.
Roll dice. Roll as many any whichever kind you want. You have a computer. The odds can be tricky to figure out, but the odds you think you want are usually wrong anyway. so just mess around until it looks good.
Suppose you want 5-10, with the middle (7.5) very common. To make it easier, center it on 0: think of it as 7.5 + (-2.5 to 2.5)
The more dice you roll, the tighter it gets. How about 5 dice. Each die rolls 1/5th of the amount, so they each roll (-0.5 to 0.5):
int num=7.5f; // start at center of the 5-10
for(int d=0;d<5;d++)
num+=Random.Range(-0.5f, 0.5f);
After a few tries, you can work out the center is just the average: (min+max)/2. And the die +/- is (max-min)/(2howManyDice). So, to roll 10-20 using 3 dice is 15 + 3random(-1.66, +1.66)
If you need integers, you have to figure the dice by hand. 10-20 with 3 dice could be 15+(-2 to 2)+(-2 to 2)+(-1 to 1)
Or, if you hate that, just add regular dice. 10-20 could be (3-6)+(3-7)+(4-7).
