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    or maybe, 'looking for a curve'

    Basically im modelling some situation and I need a curve which is asymptotic to y = 1 as x < ~A and asymptotic to y = 0 as x becomes larger.

    Anyone have any ideas?

    Obviously its not Ae^(-kx) but I think it would involve exponentials...

    Thanks so much

    For what its worth ill rep you if you find an equation which works

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    (Original post by 7589200)
    ...
    Does it need to reach 1 as x-->0, or to -infinity? Graph is confusing.

    If it's -infinity:
    An inverse tan would be a good starting point; a few transformations and it will meet your criteria.
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    (Original post by ghostwalker)
    Does it need to reach 1 as x-->0, or to -infinity? Graph is confusing.

    If it's -infinity:
    An inverse tan would be a good starting point; a few transformations and it will meet your criteria.
    Nah it needs to be close to 1, not reach it, as x=0.

    so 1 as it heads to minus infinity and 0 as it heads to positive infinity
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    (Original post by 7589200)
    Nah it needs to be close to 1, not reach it, as x=0.

    so 1 as it heads to minus infinity and 0 as it heads to positive infinity
    What about something like y=0.5(1-\tanh(x-k)) ?
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    (Original post by Mr M)
    What about something like y=0.5(1-\tanh(x-k)) ?
    With k = 2 that's pretty much exactly what I wanted

    thanks very much!
 
 
 
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