[R] how to fit exponential curve such as a*b^t in r?

[Jeff Newmiller]

Read the examples section of

?nls

You probably need to provide a start list of values.

There are some points you should note from the Posting Guide mentioned in the footer of emails on this list: this is not a homework help forum, you should provide a reproducible example, and you should not post in HTML format.
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Sent from my phone. Please excuse my brevity.

"水静流深" <1248283536 at qq.com> wrote:
>input <- "    
>      t    y    
>     1  5.3    
>     2  7.2    
>     3  9.6    
>     4 12.9    
>     5 17.1    
>     6 23.2"         
>    dat<-read.table(textConnection(input),header=TRUE,sep="")    
>    t<-dat[,1]    
>    y<-dat[,2]   
>
>`y=3.975*(1.341^t)` is the resule of fit,how can i use `nls` function
>to get it?
>	[[alternative HTML version deleted]]
>
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