dankelley/oce — Issue #201: adp distance calculation
Author: dankelley
Created: 2012-03-05 16:32:12+00:00
State: open

I am confused on the calculation of ``distance`` in the ADP code. For example, for an RDI unit on my own machine,

library(oce)
beam <- read.oce("/data/archive/sleiwex/2008/moorings/m09/adp/rdi_2615/raw/adp_rdi_2615.000",
from=as.POSIXct("2008-06-26", tz="UTC"), to=as.POSIXct("2008-06-27", tz="UTC"), by="10:00",
latitude=47.88126, longitude=-69.73433)
plot(beam, which='u1')
lines(beam[["time"]], beam[["pressure"]], lwd=3, col='blue')
lines(beam[["time"]], beam[["pressure"]]/cos(20*pi/180), lwd=3, col='green')

the green line seems more reasonable, which suggests that the formula in the present code is calculating distances along beams, as opposed to along the central axis of the viewing cone.