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", latitude=NA, longitude=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.
latitude
latitude of observation (stored in metadata)
longitude
longitude of observation (stored in metadata)
Value
- An object of
class "lisst", which is a
list with slots as detailed below. - dataa data frame 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.} - metadataa 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. - processingLoga processingLog 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.References
The LIST-100 users guide (version 4.65), which provided the
information for this function, was downloaded in late May 2012, from
http://www.sequoiasci.com/products/fam_LISST_100.aspx.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.