(New page: We create a variables : A ~ exp(1/2) w ~ unif[0, 2pi] then let : <math>X = \sqrt(A)cos(w)</math> <math>Y = \sqrt(A)sin(w)</math>)
 
 
(10 intermediate revisions by the same user not shown)
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We create a variables :  
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We create variables :  
  
 
A ~ exp(1/2)
 
A ~ exp(1/2)
 +
 
w ~ unif[0, 2pi]
 
w ~ unif[0, 2pi]
  
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<math>X = \sqrt(A)cos(w)</math>
 
<math>X = \sqrt(A)cos(w)</math>
 +
 
<math>Y = \sqrt(A)sin(w)</math>
 
<math>Y = \sqrt(A)sin(w)</math>
 +
 +
Then you can go through the proof and show that the PDF of X and Y ~ N[0, 1]
 +
(The proof involves calculating the CDF of A and w, then the joint CDF of A and w to get the CDF of X or Y, then differentiat to get the PDF of X or Y)
 +
 +
Therefore, in c to produce a random variable with a gaussian distribution you simply do the following
 +
 +
<math>\sqrt(A) cos(drand48())</math>
 +
 +
where A is what you solved for from part b of problem 1

Latest revision as of 17:03, 20 October 2008

We create variables :

A ~ exp(1/2)

w ~ unif[0, 2pi]

then let :

$ X = \sqrt(A)cos(w) $

$ Y = \sqrt(A)sin(w) $

Then you can go through the proof and show that the PDF of X and Y ~ N[0, 1] (The proof involves calculating the CDF of A and w, then the joint CDF of A and w to get the CDF of X or Y, then differentiat to get the PDF of X or Y)

Therefore, in c to produce a random variable with a gaussian distribution you simply do the following

$ \sqrt(A) cos(drand48()) $

where A is what you solved for from part b of problem 1

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