R help - Jun 2007 - inverse cumulative distribution

hi all:

ecdf() is the empirical cumulative distribution function, but I need the 
INVERSE cumulative distribution.

how can I calculate it?

thank you in advance

/salva

On 6/4/07, salcaraz at obelix.umh.es <salcaraz at obelix.umh.es>
wrote:
> hi all:
>
> ecdf() is the empirical cumulative distribution function, but I need the
> INVERSE cumulative distribution.
>
> how can I calculate it?
Two ways:
1. eccdf <- function(x) { return( 1 - ecdf(x)(x) ) }
  This returns an array of element, not an object (like ecdf)
2. Cut&Paste "ecdf" code (from R write "ecdf" and then
Enter) into a
new function "eccdf" (or whatever u want); in place of
"cumsum(...)"
write "1-cumsum(...)", and rename the class name "ecdf"
in"eccdf" (or
other). Note, doing "plot(eccdf(x))" you will not get similar result
to "plot(ecdf(x))" since the last one call "plot.ecdf". By
the way you
can write a "plot.eccdf" function.

-- Marco
>
> thank you in advance
>
> /salva
>
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>

Doesn't quantile() do what you want?

HTH,
Ranjan
> hi all:
> 
> ecdf() is the empirical cumulative distribution function, but I need the 
> INVERSE cumulative distribution.
> 
> how can I calculate it?
> 
> thank you in advance
> 
> /salva
> 
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>