[R] Unix commands on R

I am using R on unix. While in R how do I execute the unix shell commands? Is there a way to do it? I am executing a function in R and the matrix resulting from the function has to be passed on as an input to unix command. Any directions will be helpful. Thanks, Suman [[alternative HTML

[R] lsmeans in R

I need help with calculating lsmeans (adjusted means) of different terms in a linear model including the main effect and the interaction effect terms. I use lm to run the linear models...I previously noted from literature that that "effects" package can be used to generate lsmeans. But I tried to u

[R] Conversion - lowercase to Uppercase letters

I would like to know how to convert a string with characters to all uppercase or all lowercase? If anyone could let me know if there exists a function in R for the conversion, that will be very helpful. Regards, Suman [[alternative HTML version deleted]] _

[R] correlation matrix - large dataset

Hello, I have a dataset with 20,000 variables.and I would like to compute a pearson correlation matrix which will be 2*2. The cor() function doesnt work in this case due to memory problem. If you have any ideas regarding a feasible way to compute correlations on such a huge dataset, please