Like Tree1Likes
  • 1 Post By grumpy

Gaussian Normal Dist. Formula

This is a discussion on Gaussian Normal Dist. Formula within the C Programming forums, part of the General Programming Boards category; Hey guys, I'm writing a program to display a histogram of 1000 Gaussian distributed numbers. I've generated the numbers using ...

  1. #1
    Registered User
    Join Date
    Feb 2013
    Posts
    5

    Gaussian Normal Dist. Formula

    Hey guys, I'm writing a program to display a histogram of 1000 Gaussian distributed numbers. I've generated the numbers using rand and now need to transform them. I have found the following formula to use

    f(x) = exp(-x^2 / (2*sigma^2)) / sqrt(2*pi*sigma)

    and I am unsure how to implement this into a function.

    Any help would be appreciated! Thanks.

  2. #2
    Registered User
    Join Date
    Jun 2005
    Posts
    6,198
    The values returned by rand() typically approximate a uniform distribution. (Although the quality of implementation varies between libraries).

    Google for techniques to convert a uniform distribution to a gaussian distribution. You will find plenty of information. It is not as simple as simply plugging in the formula you showed (which is the distribution function for a gaussian).
    Right 98% of the time, and don't care about the other 3%.

  3. #3
    Registered User
    Join Date
    Feb 2013
    Posts
    5
    I've come across the Box-Muller method, and it seems like the best way to do it, but to be honest, i'm not really sure how to apply that. A general over view of the process would help greatly.

  4. #4
    Registered User
    Join Date
    Jun 2005
    Posts
    6,198
    First link to google with the string "box-muller" is this.

    True, it doesn't provide code, but if your want to use the Box-Muller transform, the information is there. The mathematics is pretty simple.
    Crossfire likes this.
    Right 98% of the time, and don't care about the other 3%.

Popular pages Recent additions subscribe to a feed

Similar Threads

  1. Gaussian Noise
    By DeliriumCordia in forum C Programming
    Replies: 7
    Last Post: 09-24-2012, 02:38 AM
  2. Gaussian Elimination program
    By whatever125 in forum C++ Programming
    Replies: 1
    Last Post: 04-06-2011, 05:11 AM
  3. Normal maps: Get normal x/y/z from color
    By Devils Child in forum Game Programming
    Replies: 2
    Last Post: 08-09-2009, 12:01 PM
  4. Gaussian elimination in C
    By Meander14 in forum C Programming
    Replies: 2
    Last Post: 09-26-2007, 03:43 AM
  5. Gaussian Elimination
    By Fiverz in forum C Programming
    Replies: 1
    Last Post: 02-05-2003, 11:59 AM

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21