function to filter identical data.fames using less than (<) and greater than (>)
You ask me to provide code when you have only described your solution rather than your problem. That limits my options more than I care to allow for investing my time.
When I think of problems that require repetitive subsetting I tend to look for solutions involving aggregation (?aggregate, ?plyr::ddply), which requires creating one or more grouping columns which can be formulated with the cut function or with logical indexed assignment (e.g. a sequence of statements something like eg$grpcol[with(eg,grpcol!="Default" & A<1 & B<1)] <- "ABTooLow").
So... what is your problem?
---------------------------------------------------------------------------
Jeff Newmiller The ..... ..... Go Live...
DCN:<jdnewmil at dcn.davis.ca.us> Basics: ##.#. ##.#. Live Go...
Live: OO#.. Dead: OO#.. Playing
Research Engineer (Solar/Batteries O.O#. #.O#. with
/Software/Embedded Controllers) .OO#. .OO#. rocks...1k
---------------------------------------------------------------------------
Sent from my phone. Please excuse my brevity.
Karl Brand <k.brand at erasmusmc.nl> wrote:
Hi Jeff, Subset is indeed what's reuqired here. But using it every time it's needed was generating excessive amounts of obtuse code. So for the sake of clarity and convenience i wanted a wrapper function to replace these repetitious subsets. Although Rui's example works just fine, love to see any idiomatic ways you might attempt this (also for the sake of improving my grasp of R). Cheers, Karl On 06/12/12 15:57, Jeff Newmiller wrote:
You have not indicated why the subset function is insufficient for
your needs...
---------------------------------------------------------------------------
Jeff Newmiller The ..... ..... Go
Live...
DCN:<jdnewmil at dcn.davis.ca.us> Basics: ##.#. ##.#. Live
Go...
Live: OO#.. Dead: OO#..
Playing
Research Engineer (Solar/Batteries O.O#. #.O#. with /Software/Embedded Controllers) .OO#. .OO#.
rocks...1k
---------------------------------------------------------------------------
Sent from my phone. Please excuse my brevity. Karl Brand <k.brand at erasmusmc.nl> wrote:
Esteemed UseRs, I've got many biggish data frames which need a lot subsetting, like
in
this example: # example eg <- data.frame(A = rnorm(10), B = rnorm(10), C = rnorm(10), D = rnorm(10)) egsub <- eg[eg$A < 0 & eg$B < 1 & eg$C > 0, ] egsub egsub2 <- eg[eg$A > 1 & eg$B > 0, ] egsub2 # To make this clearer than 1000s of lines of extractions with [] # I tried to make a function like this: # func(data="eg", A="< 0", B="< 1", C="> 0") # Which would also need to be run as # func(data="eg", A="> 1", B="> 0", C=NA) #end Noteably: -the signs* "<" and ">" need to be flexible _and_ optional -the quantities also need to be flexible -column header names i.e, A, B and C don't need flexibility, i.e., can remain fixed * "less than" and "greater than" so google picks up this thread Once again i find just how limited my grasp of R is...Is do.call()
the
best way to call binary operators like < & > in a function? Is an ifelse statement needed for each column to make filtering on it optional? etc.... Any one with the patience to show their working version of such a funciton would receive my undying Rdulation. With thanks in advance, Karl