aurora: Aurora Australis voyage track

Description Format Details References Examples

Description

Voyage track data from the Aurora Australis

Format

aurora A data frame with 3 columns. The columns represent

LONGITUDE_DEGEAST Longitude values
LATITUDE_DEGNORTH Latitude values
DATE_TIME_UTC Date-time values (POSIXct)

Details

This is a sample of the "Aurora Australis Voyage 3 2012/13 Track and Underway Data".

References

http://gcmd.nasa.gov/KeywordSearch/Metadata.do?Portal=amd_au&MetadataView=Full&MetadataType=0&KeywordPath=&OrigMetadataNode=AADC&EntryId=201213030

Examples

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## Not run: 
## These data were obtained like this
base <- "http://gcmd.gsfc.nasa.gov/KeywordSearch/RedirectAction.do?target"
b1 <-   "=F4t70bSf87FLsT1TNxR9TSPS74xbHAdheLQcH5Z5PMmgzJ9t%2Bi%2FEs1e8Fl61"
b2 <-   "MPhKjo9qxb2f9wyA%0D%0AoE1kjJ8AMcpFlMMRH7Z6umgNLsGMnWPeQdU7mZHMp%2"
b3 <-   "FtqMpahIrde%2F%2B9%2FZWAkIFrh2bhIiNfl4I9J%0D%0A5KBX9g5Wf7I9JdOgqY"
b4 <-   "bDdpj0iM1K%2BA%3D%3D"
aurora2013 <- read.csv(paste(base, b1, b2, b3, b4, collapse = ""), stringsAsFactors = FALSE)
aurora2013$DATE_TIME_UTC <- as.POSIXct(aurora2013$DATE_TIME_UTC, tz = "GMT")
## get a daily sample
aurora <- aurora2013[,c("LONGITUDE_DEGEAST", "LATITUDE_DEGNORTH", "DATE_TIME_UTC")]
aurora <- aurora[!duplicated(format( aurora$DATE_TIME_UTC, "%Y-%j")), ]
aurora <- aurora[order(aurora$DATE_TIME_UTC), ]
save(aurora, file = "aurora.rda")

## End(Not run)

mdsumner/sctrip documentation built on May 22, 2017, 3:21 a.m.