R help - Sep 2011 - Does replacing some values of a zoo object by NA reduce it's size ?

Dear R-helpers,

Please have a look at the following. f1 is the same as f2 except that it has
some values replaced by NA. But it's corresponding file is slightly bigger
than the file containing f2. Could someone please tell me if this is an
anomaly ?
> load("file1")
> ls()
[1] "f1"
> load("file2")
> ls()
[1] "f1" "f2"
>
> dput(f1)
structure(c(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, NA, NA, NA, 2, 2,
2, NA, NA, NA, NA), .Dim = c(10L, 2L), .Dimnames = list(NULL,
    c("v1", "l1")), index = 1:10, class =
"zoo")
> dput(f2)
structure(c(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 2, 2, 2, 2, 2, 2,
2, 2, 2, 2), .Dim = c(10L, 2L), .Dimnames = list(NULL, c("v1",
"l1")), index = 1:10, class = "zoo")

-rw-r--r-- 1 ashimkapoor ashimkapoor 192 2011-09-27 11:08 file1
-rw-r--r-- 1 ashimkapoor ashimkapoor 179 2011-09-27 11:08 file2

Best Regards,
Ashim.

	[[alternative HTML version deleted]]

It is not an anomaly.  The object is the same size 
(object.size(f1)==object.size(f2)); its file representation is different.

On 27/09/2011 07:00, Ashim Kapoor wrote:
> Dear R-helpers,
>
> Please have a look at the following. f1 is the same as f2 except that it
has
> some values replaced by NA. But it's corresponding file is slightly
bigger
> than the file containing f2. Could someone please tell me if this is an
> anomaly ?
>
>> load("file1")
>> ls()
> [1] "f1"
>> load("file2")
>> ls()
> [1] "f1" "f2"
>> dput(f1)
> structure(c(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, NA, NA, NA, 2, 2,
> 2, NA, NA, NA, NA), .Dim = c(10L, 2L), .Dimnames = list(NULL,
>      c("v1", "l1")), index = 1:10, class =
"zoo")
>> dput(f2)
> structure(c(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 2, 2, 2, 2, 2, 2,
> 2, 2, 2, 2), .Dim = c(10L, 2L), .Dimnames = list(NULL, c("v1",
> "l1")), index = 1:10, class = "zoo")
>
> -rw-r--r-- 1 ashimkapoor ashimkapoor 192 2011-09-27 11:08 file1
> -rw-r--r-- 1 ashimkapoor ashimkapoor 179 2011-09-27 11:08 file2
>
> Best Regards,
> Ashim.
>
> 	[[alternative HTML version deleted]]
>
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