s2dverification (version 2.5.0)

Trend: Computes Trends

Description

Computes the trend along the posTR dimension of the matrix var by least square fitting, and the associated an error interval. Provide also the detrended data. The confidence interval relies on a student-T distribution.

Usage

Trend(var, posTR = 2, interval = 1)

Arguments

var

Matrix of any number of dimensions up to 10.

posTR

Position along which to compute the trend.

interval

Number of months/years between 2 points along posTR dimension. Default = 1. The trend would be provided in number of units per month or year.

Value

$trend

Same dimensions as var except along the posTR dimension which is replaced by a length 3 dimension, corresponding to the lower limit of the 95% confidence interval, trends and the upper limit of the 95% confidence interval for each point of the matrix along all the other dimensions.

$detrended

Same dimensions as var with linearly detrended var along the posTR dimension.

Examples

# Load sample data as in Load() example:
example(Load)
months_between_startdates <- 60
trend <- Trend(sampleData$obs, 3, months_between_startdates)
PlotVsLTime(trend$trend, toptitle = "trend", ytitle = "K / (5 year)",
            monini = 11, limits = c(-1,1), listexp = c('CMIP5 IC3'),
            listobs = c('ERSST'), biglab = FALSE, hlines = 0,
            fileout = 'tos_obs_trend.eps')
PlotAno(trend$detrended, NULL, startDates, 
        toptitle = 'detrended anomalies (along the startdates)', ytitle = 'K',
        legends = 'ERSST', biglab = FALSE, fileout = 'tos_detrended_obs.eps')