[R] Getting a column of values from a list - think I'm doing it the hard way

Jason Rupert jasonkrupert at yahoo.com
Thu Jun 4 04:45:23 CEST 2009


Example code it shown below.

I think I am doing this the hard way.  I'm just trying to get the full year value from an array of dates.  An example array is shown below.  Right now, I'm using a "for" loop to pull the year out of a list where the dates were split up into their individual components.  

This seems to work, but just wondering if there is an easier way.  

Thanks for any insights. 

#*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~*~
HouseDates <- c("02/27/90", "02/27/91", "01/14/92", "02/28/93", "02/01/94", "02/01/95", "02/01/96")

# ?as.Date
HouseDatesFormatted<-as.Date(HouseDates, "%m/%d/%y")

HouseDatesFormatted

HouseDatesList<-strsplit(as.character(HouseDatesFormatted), "-", fixed=TRUE)

HouseYear_array<-NULL
length_array<-length(HouseDatesList)
for(ii in 1:length_array)
{   
        HouseYear<-HouseDatesList[[ii]][1]
        
        HouseYear_array<-c(HouseYear_array, HouseYear)
}

as.character(HouseYear_array)

# Desired:
# [1] "1990" "1991" "1992" "1993" "1994" "1995" "1996"




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