| read.fortran {utils} | R Documentation |
Read fixed-format data files using Fortran-style format specifications.
read.fortran(file, format, ..., as.is = TRUE, colClasses = NA)
file |
File or connection to read from |
format |
Character vector or list of vectors. See ‘Details’ below. |
... |
Other arguments for |
as.is |
Keep characters as characters? |
colClasses |
Variable classes to override defaults. See
|
The format for a field is of one of the following forms: rFl.d,
rDl.d, rXl, rAl, rIl, where l is
the number of columns, d is the number of decimal places, and
r is the number of repeats. F and D are numeric
formats, A is character, I is integer, and X
indicates columns to be skipped. The repeat code r and decimal
place code d are always optional. The length code l is
required except for X formats when r is present.
For a single-line record, format should be a character
vector. For a multiline record it should be a list with a character
vector for each line.
Skipped (X) columns are not passed to read.fwf, so
colClasses, col.names, and similar arguments passed to
read.fwf should not reference these columns.
A data frame
read.fortran does not use actual Fortran input routines, so
the formats are at best rough approximations to the Fortran ones.
In particular, specifying d > 0 in the F or D
format will shift the decimal d places to the left, even if
it is explicitly specified in the input file.
read.fwf, read.table, read.csv
ff <- tempfile()
cat(file=ff, "123456", "987654", sep="\n")
read.fortran(ff, c("F2.1","F2.0","I2"))
read.fortran(ff, c("2F1.0","2X","2A1"))
unlink(ff)
cat(file=ff, "123456AB", "987654CD", sep="\n")
read.fortran(ff, list(c("2F3.1","A2"), c("3I2","2X")))
unlink(ff)
# Note that the first number is read differently than Fortran would
# read it:
cat(file=ff, "12.3456", "1234567", sep="\n")
read.fortran(ff, "F7.4")
unlink(ff)