double_serie: Double the length of a data series for the FAST algoritm
Description
This function is used internally for the FAST-algorithm. It duplicates
the length of a data series assuming that the second part is a mirror
image of the first part
Usage
double_serie(x)
Arguments
x
x is the data series to make longer
Value
If x=c(1,2,3,4) the returned vector is
c(1,2,3,4,3,2,1)
Details
This function reverses the model output series from a
number of model runs for the FAST analysis and appends it to the
original series. The last element of the existing series is not
duplicated during this process.
This is required in order to process the model run results for the
FAST analysis with the fft function.