read.lisst: Read a LISST data file
Description
Read a LISST data file, producing an object of type lisst
.Usage
read.lisst(file, year=0, tz="UTC", longitude=NA, latitude=NA)
Arguments
file
a connection or a character string giving the name of the
file to load.
year
year in which the measurement of the series was made.
longitude
longitude of observation (stored in metadata)
latitude
latitude of observation (stored in metadata)
Value
- An object of
class
"lisst"
, which is a list
with slots as detailed below. data
: a list containing columns named C1
to C32
,
which are volume concentrations (in microliters per liter) for size
classes 1 through 32, along with
lts
(laser transmission sensor, column 33),
voltage
(battery voltage in calibrated units, column 34),
aux
(external auxiliary input 1 in calibrated units, column 35),
lrs
(laster reference sensor in calibrated units, column 36),
pressure
(pressure in dbar, column 37),
temperature
(in degrees C, column 38),
dayhour
(day*100 +hour, column 39),
minutesecond
(minute*100+second, column 40),
transmission
(computed percent optical transmission over path, column 41),
beam
(computed beam-C in units of 1/m, column 42),
and
time
{a POSIXct time calculated from dayhour
and
minuteseconds
, using the year
specified as an argument,
or the present year, if the year was not given, and using timezone
tz
.}metadata
: a list containing the following items
filename
, the name of the file holding the data, latitude
, the
latitude of the observations, and longitude
, the longitude of the
observations.processingLog
: a log of processing, in the standard oce
format.
Details
The file should contain 42 columns, with no header. If there are fewer
than 42 columns, an error results. If there are more, only the first 42 are
used. Note that read.oce
can recognize LISST files by their
having a name ending in ".asc"
and by having 42 elements on the first
line. Even so, it is preferred to use the present function, because it gives
the opportunity to specify the year and timezone, so that times can be
calculated properly.See Also
The documentation for lisst-class
explains the structure
of lisst
objects, and also outlines the other functions dealing with
them. In particular, read.lisst
uses as.lisst
to
create the LISST object that is returned.