Density Distributions

Specific Domains Statistics
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1

Hello, im trying to get the array of the discrete probability distribution of a normal distribution:

i have tried:

d = Normal() #standard
a = rand(d,1000)
x = pdf.(d, a) #even with just pdf(d,a)
plot(x)

but its not working

2

first do
using Distributions, Plots
then your code works on my Julia 1.5.3 (Windows)

3

can you post what it is returning you (the plot)?

4

I don’t know what you expect, but if you change your code to

using Distributions, Plots
d = Normal() #standard
x = sort!(rand(d,1000))
y = pdf(d, x) #even with just pdf(d,a)
plot(x,y)

I see a nice approximation of a gaussian bell curve.

5

thanks thats what i wanted, i dont understand why using sort!() works though

6

i dont understand why using sort!() works though

for plotting a series, you want x to be ordered (typically increasing order)

7

I intentionally changed the names of your variables. Think about a function f(x) = x You basically told Julia to roll a dice several times and plot the result. Assume you rolled x={2,-1,3}. Plotting x in that order clearly is not the graph of f. Ordering the arguments gives the correct result.
In the same spirit, you could change

x=sort!(rand(d,1000))

to

x=-3:0.1:3

and plot the result. But of course it is still unclear what you wanted to achieve in the first place.
Note that there is not a clear notion of a discrete normal distribution. And hence the terminology of getting the one array of the probabliity distribution is also a bit unclear.