R help - May 2009 - How to replace Inf by zero?

Hi R users,

Someone knows how to replace Infinite value by zero. I have a vector with
some Inf value and I want to substitute these values by zero to get the mean
of the components of the vector.

Any idea?

Many thanks,

Marlene.

	[[alternative HTML version deleted]]

Dear Marlene,

Have a look at is.infinite(). Replacing them by zero is not a very
bright idea if you want the mean of the resulting vector. Have a look at
the example below.

#create a vector
x <- rnorm(100, mean = 1000)
#replace 20 values with Inf
x[sample(seq_along(x), 20, replace = FALSE)] <- Inf
mean(x)

#replace Inf with zero
y <- x
y[is.infinite(y)] <- 0
#replace inf with NA
x[is.infinite(x)] <- NA
mean(x, na.rm = TRUE)
mean(y) 

HTH,

Thierry

------------------------------------------------------------------------
----
ir. Thierry Onkelinx
Instituut voor natuur- en bosonderzoek / Research Institute for Nature
and Forest
Cel biometrie, methodologie en kwaliteitszorg / Section biometrics,
methodology and quality assurance
Gaverstraat 4
9500 Geraardsbergen
Belgium
tel. + 32 54/436 185
Thierry.Onkelinx at inbo.be
www.inbo.be

To call in the statistician after the experiment is done may be no more
than asking him to perform a post-mortem examination: he may be able to
say what the experiment died of.
~ Sir Ronald Aylmer Fisher

The plural of anecdote is not data.
~ Roger Brinner

The combination of some data and an aching desire for an answer does not
ensure that a reasonable answer can be extracted from a given body of
data.
~ John Tukey

-----Oorspronkelijk bericht-----
Van: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org]
Namens marlene marchena
Verzonden: vrijdag 29 mei 2009 15:18
Aan: R-help at r-project.org
Onderwerp: [R] How to replace Inf by zero?

Hi R users,

Someone knows how to replace Infinite value by zero. I have a vector
with some Inf value and I want to substitute these values by zero to get
the mean of the components of the vector.

Any idea?

Many thanks,

Marlene.

	[[alternative HTML version deleted]]

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Thanks a lot Andrea, it works!

Marlene.

2009/5/29 Andrea Weidacher <da09ml@yahoo.de>
> Hi Marlene,
>
> try this:
>
> x[which(x==Inf)] <- 0
>
> Andrea.
>
> ------------------------------
> *Von:* marlene marchena <marchenamarlene@gmail.com>
> *An:* R-help@r-project.org
> *Gesendet:* Freitag, den 29. Mai 2009, 15:17:57 Uhr
> *Betreff:* [R] How to replace Inf by zero?
>
> Hi R users,
>
> Someone knows how to replace Infinite value by zero. I have a vector with
> some Inf value and I want to substitute these values by zero to get the
> mean
> of the components of the vector.
>
> Any idea?
>
> Many thanks,
>
> Marlene.
>
>     [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help@r-project.org 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.
>
>
	[[alternative HTML version deleted]]

marlene marchena <marchenamarlene <at> gmail.com> writes:
> 
> Hi R users,
> 
> Someone knows how to replace Infinite value by zero. I have a vector with
> some Inf value and I want to substitute these values by zero to get the
mean
> of the components of the vector.
> 
> Any idea?
> 
> Many thanks,
> 
> Marlene.


Hi Marlene,

if you just want to calculate the mean of the non-infinite values, you can use
this statement:

mean(x[!is.infinite(x)])


Sven