search for: desviation

Hello all, I'm trying to calculate the standar desviation and I'm using the function sd(x,na.rm=TRUE) and I have this error:? Error in var(x, na.rm = na.rm) : no complete element pairs . Why happen this?, What can I do to solve it?. x is list of three numbers which I have from a table. Thanks so much from Spain Carlos Morales Diego

Hello!!! I have a question about clustering. I'll present my problem first. I have a simulation of a protein trayectory (a file with a time series of protein 3D-coordinates), from it I can calculate the Root Mean Square desviation (RMSD) beetween any pair of structures in the trayectory, which is a rough idea of 3D similarity beetween them. If for every conformation (trayectory frame) I calculate the RMSD with all other frames in the trayectory, I get a RMSD matrix, which is the data i have now. In some published works a...