Converts matrix to vector time series for various analyses

First aggregates multivariate matrix time series by year. Then converts to a vector time series in which “seasons” correspond to these annualized values for the original variables.

mts2ts(x, seas = 1:frequency(x), na.rm = FALSE)

Arguments

x: An object of class "mts"
seas: Numeric vector of seasons to aggregate in original time series.
na.rm: Should missing data be ignored when aggregating?

Value

A vector time series

Details

The seas parameter enables focusing the subsequent analysis on seasons of special interest, or to ignore seasons where there are too many missing data. The function can be used in conjunction with seaKen to conduct a Regional Kendall trend analysis. Sometimes just plotting the resulting function can be useful for exploring a spatial transect over time.

Author

Alan Jassby, James Cloern

Examples


## Quick plot a spatial transect of chlorophyll a during the 
## spring bloom period (Feb-Apr) for each year.
y <- mts2ts(sfbayChla, seas = 2:4)
plot(y, type = 'n')
abline(v = 1978:2010, col = 'lightgrey')
lines(y, type = 'h')