search for: advect

...e just started coding in R and do not know fortran). I need to extract this because it will be used in further calculations, and it needs to be verified to make sure that I am using the right process. I would like to use this to remove the seasonal component of a time series to investigate the advective transport of oxygen and the local production. I tried d <- stl(data, s.window="periodic") d$trend and I get NULL thanks Stephen -- Let's not spend our time and resources thinking about things that are so little or so large that all they really do for us is puff us up and ma...

Hi, I am trying to solve a model that consists of rather stiff ODEs in R. I use the package ODEsolve (lsoda) to solve these ODEs. To speed up the integration, the jacobian is also specified. Basically, the model is a one-dimensional advection-diffusion problem, and thus the jacobian is a tridiagonal matrix. The size of this jacobian is 100*100. In the original package LSODA it is possible to specify that the jacobian is banded, which makes its inversion very efficient. However, this feature seems to have been removed in the R...

...e continuous without interuption is 53 days. I would like to look at the power spectral density at each of these sites (most likely one day will be the overridding trend due to photosynthesis and respiration). I would also like to look at the cross spectrums between to contiguous site to look for advective transport from the upstream sections.I have used spectrum to get a periodogram. This I don't believe is the power spectral density. If it is I am unsure how to determine the # in the span argument to smooth the periodogram. I imagine that I am overlooking something- I appreciate all of y...