
Reads some meteorological file formats used by the Environment
Canada (see reference 1). Since the agency does not publish the
data formats, this function had to be based on some sample files, and it
is likely to fail if Environment Canada changes their file format. For
example, a change was required in October 2019, to accommodate changes
to the file format noticed at that time (see the notes on the type
argument).
read.met(
file,
type = NULL,
skip = NULL,
tz = getOption("oceTz"),
debug = getOption("oceDebug")
)
a character string naming a file that holds met data.
if NULL
, which is the default, then an attempt is
made to infer the type from the file contents. If this fails, it
will be necessary for the user to provide a value for the type
argument. The permitted choices are: (a) "csv"
or "csv1"
for an
old CSV format no longer provided as of October 2019,
(b) "csv2"
for a CSV format noticed on the Environment Canada
website in October 2019 (but note that the paired metadata file
is ignored), and (c) "xml2"
for an XML format that was noticed
on the Environment Canada website in October 2019.
number of lines of header that occur before the actual
data. This is ignored unless type
is "csv"
or "csv1"
, in which case
a non-NULL
value of skip
is taken as the number of lines preceding
the columnar data ... and this is only needed if read.met()
cannot
find a line starting with "Date/Time"
.
timezone assumed for time data
a flag that turns on debugging. Set to 1 to get a moderate amount of debugging information, or to 2 to get more.
Environment Canada website for Historical Climate Data
https://climate.weather.gc.ca/index_e.html
Other things related to met data:
[[,met-method
,
[[<-,met-method
,
as.met()
,
download.met()
,
met-class
,
met
,
plot,met-method
,
subset,met-method
,
summary,met-method
,
test_met_csv1.csv
,
test_met_csv2.csv
,
test_met_xml2.xml
# NOT RUN {
# The old csv format (no longer supplied by Environment Canada as of Oct 2019)
csv1 <- read.met(system.file("extdata", "test_met_vsn1.csv", package="oce"))
# The new "csv2" format (provided by Environment Canada as of Oct 2019)
csv2 <- read.met(system.file("extdata", "test_met_vsn2.csv", package="oce"))
# "xml2" format
if (requireNamespace("XML", quietly=TRUE))
xml2 <- read.met(system.file("extdata", "test_met_xml2.xml", package="oce"))
# }
# NOT RUN {
library(oce)
# Recreate data(met) and plot u(t) and v(t)
metFile <- download.met(id=6358, year=2003, month=9, destdir=".")
met <- read.met(metFile)
met <- oceSetData(met, "time", met[["time"]]+4*3600,
note="add 4h to local time to get UTC time")
plot(met)
# }
# NOT RUN {
# }
Run the code above in your browser using DataLab