Usage
import(file = file.choose(), file.type = "csv", sep = ",",
header.at = 1, data.at = 2, date = "date",
date.format = "%d/%m/%Y %H:%M", time = NULL, time.format = NULL,
tzone = "GMT", na.strings = c("", "NA"), quote = "\"", ws = NULL,
wd = NULL, correct.time = NULL, ...)Arguments
file
The name of the file to be imported. Default, file =
file.choose(), opens browser. Alternatively, the use of
read.table (in utils) also allows this to be a character
vector of a file path, connection or url.
file.type
The file format, defaults to common csv (comma
delimited) format, but also allows txt (tab delimited).
sep
Allows user to specify a delimiter if not , (csv) or
TAB (txt). For example ; is sometimes used to delineate separate
columns.
header.at
The file row holding header information or NULL if
no header to be used.
data.at
The file row to start reading data from. When generating the
data frame, the function will ignore all information before this row, and
attempt to include all data from this row onwards.
date
Name of the field containing the date. This can be a
date e.g. 10/12/2012 or a date-time format e.g. 10/12/2012 01:00.
date.format
The format of the date. This is given in R
format according to strptime. For example, a date format
such as 1/11/2000 12:00 (day/month/year hour:minutes) is given the
format %d/%m/%Y %H:%M. See examples be
time
The name of the column containing a time --- if there
is one. This is used when a time is given in a separate column and
date contains no information about time.
time.format
If there is a column for time then the
time format must be supplied. Common examples include %H:%M
(like 07:00) or an integer giving the hour, in which case the
format is %H. Again, see examples below.
tzone
The time zone for the data. In order to avoid the
complexities of DST (daylight savings time), openair assumes the
data are in GMT (UTC) or a constant offset from GMT. Users can set
a positive or negative offset in hours from GMT. For example, to
set
na.strings
Strings of any terms that are to be interpreted
as missing (NA). For example, this might be -999, or
n/a and can be of several items.
quote
String of characters (or character equivalents) the
imported file may use to represent a character field.
ws
Name of wind speed field if present if different from
ws e.g. ws = "WSPD".
wd
Name of wind direction field if present if different
from wd e.g. wd = "WDIR".
correct.time
Numerical correction (in seconds) for imported
date. Default NULL turns this option off. This can be useful if
the hour is represented as 1 to 24 (rather than 0 to 23 assumed by
R). In which case correct.time = -3600 will cor
...
Other arguments passed to read.table.