On Aug 25, 2011, at 11:24 AM, mdvaan wrote:
Hi,
I have produced a list g and I would like to reduce the amount of
information contained in each object in g.
For each matrix I would like to keep the values where the column
name equals
g[year][[1]][[x]] and the row names equals g[year][[1]][[-x]]. So in
g$`1999`$`8029`, year = 1999 and x = 8029. I have been experimenting
with
the subset function, but have been unsuccesful. Thanks for your help!
I suspect this is because you g object does not have the structure
that you imagine for it:
> str(g)
List of 3
$ 1997: num [1:4, 1:4] 3 2 1 1 2 3 0 1 1 0 ...
..- attr(*, "dimnames")=List of 2
.. ..$ B: chr [1:4] "8025" "8026" "8027" "8029"
.. ..$ B: chr [1:4] "8025" "8026" "8027" "8029"
$ 1998: num [1:4, 1:4] 2 1 1 0 1 3 1 1 1 1 ...
..- attr(*, "dimnames")=List of 2
.. ..$ B: chr [1:4] "8025" "8026" "8027" "8029"
.. ..$ B: chr [1:4] "8025" "8026" "8027" "8029"
$ 1999: num [1:5, 1:5] 2 1 1 0 0 1 3 2 0 1 ...
..- attr(*, "dimnames")=List of 2
.. ..$ B: chr [1:5] "8025" "8026" "8027" "8028" ...
.. ..$ B: chr [1:5] "8025" "8026" "8027" "8028" ...
The things you think are list indices are really in the 'dimnames'
attributes of the objects.
--
David
The result for g$`1999`$`8029` should be:
$`1999`$`8029`
B
B 8029
8026 1
8027 1
8028 1
The result for g$`1999`$`8028` should be:
$`1999`$`8028`
B
B 8028
8029 1
The result for g$`1999`$`8027` should be:
$`1999`$`8027`
B
B 8027
8025 1
8026 2
8029 1
Example:
DF = data.frame(read.table(textConnection(" A B C
80 8025 1995
80 8026 1995
80 8029 1995
81 8026 1996
82 8025 1997
82 8026 1997
83 8025 1997
83 8027 1997
90 8026 1998
90 8027 1998
90 8029 1998
84 8026 1999
84 8027 1999
85 8028 1999
85 8029 1999"),head=TRUE,stringsAsFactors=FALSE))
e <- function(y) crossprod(table(DF[DF$C %in% y, 1:2]))
years <- sort(unique(DF$C))
f <- as.data.frame(embed(years, 3))
g<-lapply(split(f, f[, 1]), e)
years<-names(g)
for (t in seq(years))
{
year=as.character(years[t])
g[[year]]<-sapply(colnames(g[[year]]), function(var)
g[[year]][g[[year]][,var]>0, g[[year]][var,]>0])
}
--
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______________________________________________
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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
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David Winsemius, MD
West Hartford, CT
______________________________________________
R-help@r-project.org mailing list
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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
