[R] if else for cumulative sum error

[David Winsemius]

On Dec 2, 2014, at 12:26 PM, Jefferson Ferreira-Ferreira wrote:

> Thank you for replies.
> 
> David,
> 
> I tried your modified form
> 
> for (i in 1:seq_along(rownames(dadosmax))){


No. it is either 1: .... or seq_along(...). in this case perhaps 1:(nrow(dadosmax)-44 would be safer

You do not seem to have understood that you cannot use an index of i+44 when i is going to be the entire set of rows of the dataframe. There is "no there there" to quote Gertrude Stein's slur against Oakland. In fact there is not there there at i+1 when you get to the end. You either need to only go to row

>  dadosmax$enchday[i] <- if ( (sum(dadosmax$above[i:(i+44)])) >= 45) 1 else
> 0
> }
> 
> However, I'm receiving this warning:
> Warning message:
> In 1:seq_along(rownames(dadosmax)) :
>  numerical expression has 2720 elements: only the first used
> 
> I can't figure out why only the first row was calculated...

You should of course read these, but the error is not from your if-statement but rahter you for-loop-indexing.

?'if'
?ifelse


> Any ideas?
> 
> 
> 
> Em Tue Dec 02 2014 at 15:22:25, John McKown <john.archie.mckown at gmail.com>
> escreveu:
> 
>> On Tue, Dec 2, 2014 at 12:08 PM, Jefferson Ferreira-Ferreira <
>> jecogeo at gmail.com> wrote:
>> 
>>> Hello everybody;
>>> 
>>> I'm writing a code where part of it is as follows:
>>> 
>>> for (i in nrow(dadosmax)){
>>>  dadosmax$enchday[i] <- if (sum(dadosmax$above[i:(i+44)]) >= 45) 1 else 0
>>> }
>>> 
>> 
>> ​Without some test data for any validation, I would try the following
>> formula
>> 
>> dadosmax$enchday[i] <- if
>> (sum(dadosmax$above[i:(min(i+44,nrow(dadosmax)))] >= 45) 1 else 0​
>> 
>> 
>> 
>>> 
>>> That is for each row of my data frame, sum an specific column (0 or 1) of
>>> that row plus 44 rows. If It is >=45 than enchday is 1 else 0.
>>> 
>>> The following error is returned:
>>> 
>>> Error in if (sum(dadosmax$above[i:(i + 44)]) >= 45) 1 else 0 :
>>>  missing value where TRUE/FALSE needed
>>> 
>>> I've tested the ifelse statement assigning different values to i and it
>>> works. So I'm wondering if this error is due the fact that at the final of
>>> my data frame there aren't 45 rows to sum anymore. I tried to use "try"
>>> but
>>> It's simply hide the error.
>>> 
>>> How can I deal with this? Any ideas?
>>> Thank you very much.
>>> 
>>>        [[alternative HTML version deleted]]
>>> 
>>> ______________________________________________
>>> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
>>> 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.
>>> 
>> 
>> 
>> 
>> --
>> The temperature of the aqueous content of an unremittingly ogled
>> culinary vessel will not achieve 100 degrees on the Celsius scale.
>> 
>> Maranatha! <><
>> John McKown
>> 
> 
> 	[[alternative HTML version deleted]]
> 
> ______________________________________________
> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> 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.

David Winsemius
Alameda, CA, USA