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DATA MINING
Desktop Survival Guide by Graham Williams |
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Global Positioning System |
In some situations in analysing data you may actually be collecting
the data directly for analysis by R from some external device,
possibly connected through the computer's serial port.
One such example is using a global positioning system. On a GNU/Linux
system this might be connected to your serial device and in R (after
ensuring you have read access to the serial port /dev/ttyS0)
you can read your current position.
> gps <- scan(file="/dev/ttyS0", n=1, what="character")
Read 1 items
> gps
[1] "@051226122125S0341825E01500808G006+00350E0000N0000D0000"
> columns <- c("tag", "date", "time", "latitude", "longitude",
"quality", "level", "movelong", "movelat", "movevert")
> widths <- c(1, 6, 6, 8, 9, 4, 6, 5, 5, 5)
> gps.data <- read.fwf("/dev/ttyS0", widths, col.names=columns, n=1,
colClasses="character")
> gps.data
tag date time latitude longitude quality level movelong movelat movevert
1 @ 050221 122125 S0341825 E01500808 G006 +00350 E0000 N0000 D0000
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