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 Ricky 11-28-2012 09:34 PM

Exponential arrival distribution in Python

Hi all,

I am doing a project on traffic simulation. I want to introduce exponentialarrival distribution to precede this task. Therefore I want write a code in python for exponential arrival distribution. I am very new for programming and if anybody can help me on this that would be great.

Cheers,
Ricky

 David Hutto 11-28-2012 10:52 PM

Re: Exponential arrival distribution in Python

>> I am doing a project on traffic simulation. I want to introduce
>> exponential arrival distribution to precede this task. Therefore I want
>> write a code in python for exponential arrival distribution. I am very new
>> for programming and if anybody can help me on this that would be great.

First, I would suggest that you give yourself a GUI like tkinter,
wxpython to visualize the data. An average of the sequential(averaged
per 60 second intervals) traveled by drivers on the road, and at what
times.

Then, and I don't know why, but it seems you want a logarithmic, scale where:

for i in range(0,4)
print "%i = %i" % (i * 10 **i)

--
Best Regards,
David Hutto
CEO: http://www.hitwebdevelopment.com

 David Hutto 11-28-2012 10:55 PM

Re: Exponential arrival distribution in Python

I mean this one:

for i in range(0,4):
print "%i = %i" % (i * 10 **i)

--
Best Regards,
David Hutto
CEO: http://www.hitwebdevelopment.com

 Paul Rubin 11-28-2012 11:25 PM

Re: Exponential arrival distribution in Python

Ricky <rakkitha263@gmail.com> writes:
> I am doing a project on traffic simulation. I want to introduce
> exponential arrival distribution to precede this task. Therefore I
> want write a code in python for exponential arrival distribution.

I've never heard of an "exponential arrival distribution" and googling
fails. Do you mean an exponential distribution, that describes the
expected arrival times in a Poisson process? Python's "random" module
has the random.expovariate function for that:

http://docs.python.org/3/library/random.html

If you want an actual (discrete) Poisson distribution, see:

http://en.wikipedia.org/wiki/Poisson...ndom_variables

 Albert Chun-Chieh Huang 11-28-2012 11:29 PM

Re: Exponential arrival distribution in Python

Hi, Ricky,

Traffic simulation sounds like a good topic to use SimPy, which is a
discrete-event simulation library in Python,
c.f. http://simpy.sourceforge.net

Professor Norm Matloff wrote a very good tutorial on SimPy, and you can
Also, I've presented this SimPy package before, my slides might be
http://alberthuang314.blogspot.tw/20...-pyhug_26.html

In short, SimPy is a process-oriented discrete-event simulation package,
which will be easier to maintain than event-oriented discrete-event
simulation. It also contains some tools to help us to visualize
simulation data. It takes some time to study it, but if you would like to do
some simulation projects, it will definitely be a good investment! Have
fun with simulation!

with Regards,

Albert Huang

Ricky <rakkitha263@gmail.com> writes:

> Hi all,
>
> I am doing a project on traffic simulation. I want to introduce exponential arrival distribution to precede this task. Therefore I want write a code in python for exponential arrival distribution. I am very new for programming and if anybody can help me on this that would be great.
>
> Cheers,
> Ricky

 duncan smith 11-29-2012 04:24 PM

Re: Exponential arrival distribution in Python

On 28/11/12 21:34, Ricky wrote:
>
> Hi all,
>
> I am doing a project on traffic simulation. I want to introduce exponential arrival distribution to precede this task. Therefore I want write a code in python for exponential arrival distribution. I am very new for programming and if anybody can help me on this that would be great.
>
> Cheers,
> Ricky
>

Maybe you mean something like,

>>> from random import expovariate
>>> expovariate(1)

0.09133428954823608
>>> expovariate(1)

2.5388809393383407
>>>

Duncan

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