R help - Feb 2011 - help on stepfunction

Dear members,

I would like a help for extracting the values from a step function
(stepfun).
>From help(stepfun) we have the following example:
Y0<-c(1.,2.,4.,3.)
y0<-c(1.,2.,3.,4.)
sfun<-stepfun(1:3,y0,f=0)
plot(sfun)

Now, suppose instead I was given the object (*sfun*, say) from which I
wanted to extract the values generated by the function *stepfun*. More
precisely, I want to know how to get the X and Y (generated by the function
*sfun*) that are used in the graph (plot(sfun)).

Thanks in advance for helping me.

Ferreti

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On Feb 8, 2011, at 2:35 PM, Mauro Ferreira wrote:
> Dear members,
>
> I would like a help for extracting the values from a step function
> (stepfun).
>
>> From help(stepfun) we have the following example:
>
> Y0<-c(1.,2.,4.,3.)
> y0<-c(1.,2.,3.,4.)
> sfun<-stepfun(1:3,y0,f=0)
> plot(sfun)
>
> Now, suppose instead I was given the object (*sfun*, say) from which I
> wanted to extract the values generated by the function *stepfun*. More
> precisely, I want to know how to get the X and Y (generated by the  
> function
> *sfun*) that are used in the graph (plot(sfun)).
It appears that you have not yet consulted the help page for stepfun  
where this is documented:

 > ls(envir = environment(sfun))
[1] "f"      "method" "n"      "x"     
"y"      "yleft"  "yright"
 >
 >  environment(sfun)$x
[1] 1 2 3
 >  environment(sfun)$y
[1] 2 3 4
 >  environment(sfun)$yleft
[1] 1

>
> Thanks in advance for helping me.
>
> Ferreti
>
> 	[[alternative HTML version deleted]]
>
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