[PD] cumulative distribution?

[pete mcpartlan]

cdf i think, when i said flat at both ends i meant horizontal. so yeah, 
an s curve not a bell curve-

so yes cumulative gaussian distibution -i think...

sorry to clog up the list with my mathematic incompetency, but how do i 
integrate the pdf?

thanks

pete

Charles Henry wrote:

>hold on...what kind of distribution are you looking for?  the
>expression is pdf for a probability density function that flattens out
>at both ends.  the cdf (cumulative density) is obtained by integrating
>the pdf-this is the stretched 's'
>Simulating random variables by the inversion method involves taking
>the integral of your chosen pdf, and putting the values in a table. 
>Then you can pick numbers between 0 and 1 and look up the random
>variable's value.  So, what distribution do you want?
>
>Chuck
>
>On 11/9/05, pete mcpartlan <petemcpartlan at yahoo.co.uk> wrote:
>  
>
>>thanks Tebjan,
>>
>>but...its not half a cosine because it has to flatten out at both ends.
>>
>>and secondly i have no idea how to take an equation like that and
>>implement that in pd... maybe i didnt explain that i'm not too good at
>>all that maths stuff...
>>
>>thanks,
>>
>>pete
>>
>>Tebjan Halm wrote:
>>
>>    
>>
>>>>>(cos(x) + 1) * c with x inside the range -Pi to 0 and c is a constant
>>>>>that defines the output range of the curve 0 to c ...
>>>>>          
>>>>>
>>>sorry, the output range will be 0 to 2*c ... because the cos range -1
>>>to 1
>>>gets shifted upwards by the +1 to 0..2 and c scales this range ...
>>>
>>>pete mcpartlan schrieb:
>>>
>>>      
>>>
>>>>hello,
>>>>
>>>>i need help with a maths problem... i am trying to plot a cumulative
>>>>distribution curve to weight random. I have a [random] that feeds
>>>>into a chain of [moses], sililar to the markov chain example but what
>>>>i want to do is have a table dump into the right inlet of each moses
>>>>changing the weighting. so far so good. what i need help with is the
>>>>curve which needs to make it more likely for the next result to be
>>>>near the  same position. the attatched patch has an array with the
>>>>sort of function it should be... like an s stetched at both ends...
>>>>is there a way i can do this with expr? or am i going to have to type
>>>>out a list for each state? i'm sure this is probably quite a simple
>>>>maths problem... but beyond me... or other ideas? might it be simpler
>>>>to have a longer array with the curve is then plotted at different
>>>>points back into the array... but considering i'm probably going to
>>>>have 16+ of these and other stuff i want to make it as simple as
>>>>possible....
>>>>
>>>>thanks in advance and apologies for rambling a bit..
>>>>
>>>>pete
>>>>
>>>>        
>>>>
>>>      
>>>
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>
>
>--
>Charles Zachary Henry
>
>anti.dazed.med
>Med student who needs a Mickey's
>
>  
>

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