Skip to content
This repository

HTTPS clone URL

Subversion checkout URL

You can clone with HTTPS or Subversion.

Download ZIP
branch: tags/patch-upd…
Fetching contributors…

Cannot retrieve contributors at this time

file 202 lines (197 sloc) 5.81 kb
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202

R : Copyright 2003, The R Development Core Team
Version 1.7.0 Under development (unstable) (2003-01-24)

R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type `license()' or `licence()' for distribution details.

R is a collaborative project with many contributors.
Type `contributors()' for more information.

Type `demo()' for some demos, `help()' for on-line help, or
`help.start()' for a HTML browser interface to help.
Type `q()' to quit R.

> ## tests of boundary cases in read.table()
> # empty file
> file.create("foo1")
[1] TRUE
> try(read.table("foo1")) # fails
Error in read.table("foo1") : no lines available in input
> read.table("foo1", col.names=LETTERS[1:4])
[1] A B C D
<0 rows> (or 0-length row.names)
> unlink("foo1")
>
> # header only
> cat("head\n", file = "foo2")
> read.table("foo2")
    V1
1 head
> try(read.table("foo2", header=TRUE)) # fails in 1.2.3
[1] head
<0 rows> (or 0-length row.names)
> unlink("foo2")
> # header detection
> cat("head\n", 1:2, "\n", 3:4, "\n", file = "foo3")
> read.table("foo3", header=TRUE)
  head
1 2
3 4
> read.table("foo3", header=TRUE, col.names="V1")
  V1
1 2
3 4
> read.table("foo3", header=TRUE, row.names=1)
  head
1 2
3 4
> read.table("foo3", header=TRUE, row.names="row.names")
  head
1 2
3 4
> read.table("foo3", header=TRUE, row.names="head") # fails in 1.2.3
  row.names
2 1
4 3
>
> # wrong col.names
> try(read.table("foo3", header=TRUE, col.names=letters[1:4]))
Error in scan(file = file, what = what, sep = sep, quote = quote, dec = dec, :
line 1 did not have 4 elements
In addition: Warning message:
header and `col.names' are of different lengths in: read.table("foo3", header = TRUE, col.names = letters[1:4])
> unlink("foo3")
>
> # incomplete last line
> cat("head\n", 1:2, "\n", 3:4, file = "foo4")
> read.table("foo4", header=TRUE)
  head
1 2
3 4
Warning message:
incomplete final line found by readTableHeader on `foo4'
> unlink("foo4")
>
> # blank last line
> cat("head\n\n", 1:2, "\n", 3:4, "\n\n", file = "foo5")
> read.table("foo5", header=TRUE)
  head
1 2
3 4
>
> # test of fill
> read.table("foo5", header=FALSE, fill=TRUE, blank.lines.skip=FALSE) # fails in 1.2.3
    V1 V2
1 head NA
2 NA
3 1 2
4 3 4
5 NA
> unlink("foo5")
>
> cat("head\n", 1:2, "\n", 3:5, "\n", 6:9, "\n", file = "foo6")
> try(read.table("foo6", header=TRUE))
Error in read.table("foo6", header = TRUE) :
more columns than column names
> try(read.table("foo6", header=TRUE, fill=TRUE))
Error in read.table("foo6", header = TRUE, fill = TRUE) :
more columns than column names
> read.table("foo6", header=FALSE, fill=TRUE)
    V1 V2 V3 V4
1 head NA NA NA
2 1 2 NA NA
3 3 4 5 NA
4 6 7 8 9
> unlink("foo6")
>
> # test of type conversion in 1.4.0 and later.
> cat("A B C D E F\n",
+ "1 1 1.1 1.1+0i NA F abc\n",
+ "2 NA NA NA NA NA NA\n",
+ "3 1 2 3 NA TRUE def\n",
+ sep = "", file = "foo7")
> (res <- read.table("foo7"))
   A B C D E F
1 1 1.1 1.1+0i NA FALSE abc
2 NA NA NA NA NA <NA>
3 1 2.0 3.0+0i NA TRUE def
> sapply(res, typeof)
        A B C D E F
"integer" "double" "complex" "logical" "logical" "integer"
> sapply(res, class)
        A B C D E F
"integer" "numeric" "complex" "logical" "logical" "factor"
> (res2 <- read.table("foo7",
+ colClasses = c("character", rep("numeric", 2),
+ "complex", "integer", "logical", "character")))
   A B C D E F
1 1 1.1 1.1+0i NA FALSE abc
2 NA NA NA NA NA <NA>
3 1 2.0 3.0+0i NA TRUE def
> sapply(res2, typeof)
          A B C D E F
   "double" "double" "complex" "integer" "logical" "character"
> sapply(res2, class)
          A B C D E F
  "numeric" "numeric" "complex" "integer" "logical" "character"
> unlink("foo7")
>
> # should be logical
> type.convert(character(0))
logical(0)
>
> # test of comments in data files
> cat("# a test file",
+ "# line 2",
+ "# line 3",
+ "#line 4",
+ "# line 5",
+ "## now the header",
+ " a b c",
+ "# some more comments",
+ "1 2 3",
+ "4 5 6# this is the second data row of the file",
+ " # some more comments",
+ "7 8 9",
+ "# trailing comment\n",
+ file= "ex.data", sep="\n")
> read.table("ex.data", header = T)
  a b c
1 1 2 3
2 4 5 6
3 7 8 9
> unlink("ex.data")
>
> ## comment chars in headers
> cat("x1\tx#2\tx3\n1\t2\t2\n2\t3\t3\n", file = "test.dat")
> read.table("test.dat", header=T, comment.char="")
  x1 x.2 x3
1 1 2 2
2 2 3 3
> unlink("test.dat")
>
> cat('#comment\n\n#another\n#\n#\n',
+ 'C1\tC2\tC3\n"Panel"\t"Area Examined"\t"# Blemishes"\n',
+ '"1"\t"0.8"\t"3"\n', '"2"\t"0.6"\t"2"\n', '"3"\t"0.8"\t"3"\n',
+ file = "test.dat", sep="")
> read.table("test.dat")
     V1 V2 V3
1 C1 C2 C3
2 Panel Area Examined # Blemishes
3 1 0.8 3
4 2 0.6 2
5 3 0.8 3
> unlink("test.dat")
>
> cat('%comment\n\n%another\n%\n%\n',
+ 'C1\tC2\tC3\n"Panel"\t"Area Examined"\t"% Blemishes"\n',
+ '"1"\t"0.8"\t"3"\n', '"2"\t"0.6"\t"2"\n', '"3"\t"0.8"\t"3"\n',
+ file = "test.dat", sep="")
> read.table("test.dat", comment.char = "%")
     V1 V2 V3
1 C1 C2 C3
2 Panel Area Examined % Blemishes
3 1 0.8 3
4 2 0.6 2
5 3 0.8 3
> unlink("test.dat")
>
> ## end of tests
>
Something went wrong with that request. Please try again.