R: Nodal Modulation Calculations for Tidem

tidemVuf {oce} | R Documentation

## Nodal Modulation Calculations for Tidem

### Description

Carry out nodal modulation calculations for `tidem()`. This function is based directly on `t_vuf` in the `T_TIDE` Matlab package (Pawlowicz et al., 2002), which inherits from the Fortran code described by Foreman (1978).

### Usage

    tidemVuf(t, j, latitude = NULL)

### Arguments

`t` | a single time in `POSIXct()` format, with timezone `"UTC"`.
`j` | integer vector, giving indices of tidal constituents to use.
`latitude` | optional numerical value containing the latitude in degrees North. If not provided, `u` in the return value will be a vector consisting of repeated 0 value, and `f` will be a vector of repeated 1 value.

### Value

A `list` containing items named `v`, `u` and `f` as described in the `T_TIDE` documentation, as well in Pawlowicz et al. (2002) and Foreman (1978).

### Author(s)

Dan Kelley translated this from the `t_vuf` function of the `T_TIDE` Matlab package (see Pawlowicz et al. 2002).

### References

- Foreman, M. G. G., 1978. Manual for Tidal Currents Analysis and Prediction. Pacific Marine Science Report. British Columbia, Canada: Institute of Ocean Sciences, Patricia Bay.

- Pawlowicz, Rich, Bob Beardsley, and Steve Lentz, 2002. Classical tidal harmonic analysis including error estimates in MATLAB using `T_TIDE`. Computers and Geosciences, 28, 929-937.

### See Also

Other things related to tides: `[[,tidem-method`, `[[<-,tidem-method`, `as.tidem()`, `plot,tidem-method`, `predict.tidem()`, `summary,tidem-method`, `tidedata`, `tidem-class`, `tidemAstron()`, `tidem`, `webtide()`

### Examples

    ## Look up values for the M2 constituent in Halifax Harbour, Canada.
    data("tidedata")
    j  <- which(tidedata$const$name=="M2")
    tidemVuf(t=as.POSIXct("2008-01-22 18:50:24"), j=j, lat=44.63)

[Package oce version 1.2-0 Index]