I did the following but it shows a couple of error messages. Could you help
me with that? Thanks in advance.
> testdata <- read.csv("C:\\Users\\Kevin\\Desktop\\testdata.csv",
> header=TRUE)
> testdata
date day time webpage item value
1 10-Jun-09 Wed 9:40:53 MattDamon fans 613031
2 11-Jun-09 Thu 5:27:47 MattDamon fans 630242
3 11-Jun-09 Thu 9:23:23 MattDamon fans 631966
4 11-Jun-09 Thu 22:11:33 MattDamon fans 642045
5 13-Jun-09 Sat 13:07:53 MattDamon fans 669791
6 15-Jun-09 Mon 5:07:06 MattDamon fans 700180
7 15-Jun-09 Mon 13:09:43 MattDamon fans 702949
8 16-Jun-09 Tue 22:45:27 MattDamon fans 726624
9 17-Jun-09 Wed 13:08:19 MattDamon fans 734412
10 19-Jun-09 Fri 12:37:09 MattDamon fans 765057
11 20-Jun-09 Sat 12:38:36 MattDamon fans 782741
12 21-Jun-09 Sun 12:36:25 MattDamon fans 796054
13 22-Jun-09 Mon 12:39:36 MattDamon fans 809816
14 23-Jun-09 Tue 12:40:25 MattDamon fans 833996
15 27-Jun-09 Sat 12:40:36 MattDamon fans 899900
16 28-Jun-09 Sun 12:38:07 MattDamon fans 910401
17 10-Jun-09 Wed 9:40:53 MattDamon views 613031
18 11-Jun-09 Thu 5:27:47 MattDamon views 630242
19 11-Jun-09 Thu 9:23:23 MattDamon views 631966
20 11-Jun-09 Thu 22:11:33 MattDamon views 642045
21 13-Jun-09 Sat 13:07:53 MattDamon views 669791
22 15-Jun-09 Mon 5:07:06 MattDamon views 700180
23 15-Jun-09 Mon 13:09:43 MattDamon views 702949
24 16-Jun-09 Tue 22:45:27 MattDamon views 726624
25 17-Jun-09 Wed 13:08:19 MattDamon views 734412
26 19-Jun-09 Fri 12:37:09 MattDamon views 765057
27 20-Jun-09 Sat 12:38:36 MattDamon views 782741
28 21-Jun-09 Sun 12:36:25 MattDamon views 796054
29 22-Jun-09 Mon 12:39:36 MattDamon views 809816
30 23-Jun-09 Tue 12:40:25 MattDamon views 833996
31 25-Jun-09 Thu 12:38:27 MattDamon views 871237
32 26-Jun-09 Fri 12:36:12 MattDamon views 887175
33 26-Jun-09 Fri 13:36:12 MattDamon views 887195
34 27-Jun-09 Sat 12:40:36 MattDamon views 899900
35 10-Jun-09 Wed 9:40:53 AngieeJolie fans 613031
36 11-Jun-09 Thu 5:27:47 AngieeJolie fans 630242
37 11-Jun-09 Thu 9:23:23 AngieeJolie fans 631966
38 11-Jun-09 Thu 22:11:33 AngieeJolie fans 642045
39 13-Jun-09 Sat 13:07:53 AngieeJolie fans 669791
40 15-Jun-09 Mon 5:07:06 AngieeJolie fans 700180
41 16-Jun-09 Tue 22:45:27 AngieeJolie fans 726624
42 17-Jun-09 Wed 13:08:19 AngieeJolie fans 734412
43 19-Jun-09 Fri 12:37:09 AngieeJolie fans 765057
44 20-Jun-09 Sat 12:38:36 AngieeJolie fans 782741
45 21-Jun-09 Sun 12:36:25 AngieeJolie fans 796054
46 22-Jun-09 Mon 12:39:36 AngieeJolie fans 809816
47 23-Jun-09 Tue 12:40:25 AngieeJolie fans 833996
48 25-Jun-09 Thu 12:38:27 AngieeJolie fans 871237
49 26-Jun-09 Fri 12:36:12 AngieeJolie fans 887175
50 26-Jun-09 Fri 13:36:12 AngieeJolie fans 887195
51 30-Jun-09 Tue 12:36:43 AngieeJolie fans 934280
52 10-Jun-09 Wed 9:40:53 AngieeJolie views 613031
53 11-Jun-09 Thu 5:27:47 AngieeJolie views 630242
54 11-Jun-09 Thu 9:23:23 AngieeJolie views 631966
55 11-Jun-09 Thu 22:11:33 AngieeJolie views 642045
56 13-Jun-09 Sat 13:07:53 AngieeJolie views 669791
57 15-Jun-09 Mon 5:07:06 AngieeJolie views 700180
58 15-Jun-09 Mon 13:09:43 AngieeJolie views 702949
59 16-Jun-09 Tue 22:45:27 AngieeJolie views 726624
60 17-Jun-09 Wed 13:08:19 AngieeJolie views 734412
61 19-Jun-09 Fri 12:37:09 AngieeJolie views 765057
62 20-Jun-09 Sat 12:38:36 AngieeJolie views 782741
63 21-Jun-09 Sun 12:36:25 AngieeJolie views 796054
64 22-Jun-09 Mon 12:39:36 AngieeJolie views 809816
65 23-Jun-09 Tue 12:40:25 AngieeJolie views 833996
66 25-Jun-09 Thu 12:38:27 AngieeJolie views 871237
67 26-Jun-09 Fri 12:36:12 AngieeJolie views 887175
68 26-Jun-09 Fri 13:36:12 AngieeJolie views 887195
69 27-Jun-09 Sat 12:40:36 AngieeJolie views 899900
>
> library(zoo)
>
> colClasses <- c("character", "character", "numeric", "character",
> "character", "numeric")
>
> col.names <- c("date", "day", "time", "webpage", "item", "value")
>
> # z <- read.zoo("myfile.dat", skip = 1, index = as.list(1:5),
> z <- read.zoo(testdata[,1:5],as.Date(as.character(testdata[, 1])),skip =
> 1, index = as.list(1:6),
+ format = "%d/%m/%Y", col.names = col.names,
+ aggregate = function(x) tail(x, 1), colClasses = colClasses)
Error in `[.data.frame`(rval, , j) : undefined columns selected
>
> ## Now that we have read it in lets process it
>
> ## 1.
>
> # extract all Thursdays and Fridays
> z45 <- z[format(time(z), "%w") %in% 4:5,]
Error: object 'z' not found
>
> # keep last entry in each week
> # and show result on R console
> z45[!duplicated(format(time(z45), "%U"), fromLast = TRUE), ]
Error: object 'z45' not found
--
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