search for: toby_marks

Displaying 6 results from an estimated 6 matches for "toby_marks".

2006 Sep 06
7
Matrix multiplication using apply() or lappy() ?
I am trying to divide the columns of a matrix by the first row in the matrix. I have tried to get this using apply and I seem to be missing a concept regarding the apply w/o calling a function but rather command args %*% / etc. Would using apply be more efficient than this approach? I have observed examples in the archives using this type of approach. Does anybody have a snippet of a call
2006 Aug 31
2
cumulative growth rates indexed to a common starting point over n series of observations
What is the R way of computing cumulative growth rates given a series of discrete values indexed . For instance, given a matrix of 20 observations for each of 5 series (zz), what is the most straight forward technique in R for computing cumulative growth (zzcum) ? It seems for the solution I'm after might be imbedding the following cum growth rate calc as a function into a function call
2006 Jun 07
1
Fw: Help needed using lattice for area plots lpolygon, xyplot.
I am trying to learn how to use the graphics from the lattice package ( and am very new to R). I am trying to replicate the example plot referenced below, by using the lattice xyplot & lpolygon to create panels. I get what appears to be the correct shape of the filled region, but cannot get the position to overlay properly. I have attempted with various settings of position. ( i.e.
2007 Mar 13
2
RODBC Excel sqlQuery insert into
I have searched the archives for using insert into to update spreadsheets using RODBC and have come up short. So, first off, is it possible? I have put together a dummy xls table (c:\foo.xls)for exploring possibilities of RODBC. Ultimately, I am interested in replacing much of our previous use of vba macros with R ( I'd prefer elimination, but will take what I can get ). In order to
2006 Jun 29
1
Help needed understanding eval,quote,expression
I am trying to build up a quoted or character expression representing a component in a list in order to reference it indirectly. For instance, I have a list that has data I want to pull, and another list that has character vectors and/or lists of characters containing the names of the components in the first list. It seems that the way to do this is as evaluating expressions, but I seem to
2006 Jun 07
0
Help needed using lattice for area plots lpolygon, xyplot.
I am trying to learn how to use the graphics from the lattice package ( and am very new to R). I am trying to replicate the example plot referenced below, by using the lattice xyplot & lpolygon to create panels. I get what appears to be the correct shape of the filled region, but cannot get the position to overlay properly. I have attempted with various settings of position. ( i.e.