Dear all,
I have a code that looks like the following (I am sorry that this is not a 
reproducible example)


    indexSkipped<-NULL



 ....code Skipped that might alter indexSkipped


    if (length(indexSkipped)==0)
        
spatial_structure<-spatial_structures_from_measurements(DataList[[i]]$Lon,DataList[[i]]$Lat,meanVector)
 
    else
        
spatial_structure<-spatial_structures_from_measurements(DataList[[i]]$Lon[-indexSkipped],DataList[[i]]$Lat[-indexSkipped],meanVector)
 # 



What I am doing here is that I am processing files. Every files has a 
measurement table and Longtitude and Latitude fields. If one file is marked as 
invalid I keep a number of of the skipped index so to remove the element of the 
Longtitude and Latitide vectors.

1) That works correct, I was just wondering if it would be possible to remove 
some how the given if statement and initialize the indexSkipped in such a way 
so 

the DataList[[i]]$Lon[-indexSkipped],DataList[[i]]$Lat[-indexSkipped] do 
nothing, aka remove no element, in case the indexSkipped remains unchanged (in 
its initial value).

2) When u define a variable as empty, I usually use NULL, how I can check 
afterwords if that holds or not. If I use  the 

 (indexSkipped==NULL)
logical(0)

this does not return true or false. How I can do that check?


Iwould like to thank you in advance for your help

B.R
Alex
        [[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.

Reply via email to