- #1

- 16

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i have y=c-a

^{-x}*b

this is basically a transformation of y=b*a

^{x}+c

- Thread starter h00zah
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- #1

- 16

- 0

i have y=c-a

this is basically a transformation of y=b*a

- #2

fzero

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[tex] y = c - b a^x[/tex]

is the function that fits the (x,y) data, you can compute

[tex] \ln (c-y) = (\ln a) x + \ln b.[/tex]

If you can find c from the asymptotic form of y, then a plot of [tex]\ln (c-y)[/tex] vs x will be linear. You can read [tex]\ln a[/tex] from the slope and [tex]\ln b[/tex] from the intercept. You can read up on linear regression theory if you want to determine the accuracy of the fit.

- #3

fzero

Science Advisor

Homework Helper

Gold Member

- 3,119

- 289

[tex] y = c - b a^x[/tex]

is the function that fits the (x,y) data, you can compute

[tex] \ln (c-y) = (\ln a) x + \ln b.[/tex]

If you can find c from the asymptotic form of y, then a plot of [tex]\ln (c-y)[/tex] vs x will be linear. You can read [tex]\ln a[/tex] from the slope and [tex]\ln b[/tex] from the intercept. You can read up on linear regression theory if you want to determine the accuracy of the fit.

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