ruby on rails - how to pass unknown number of arguments to a function in R programming -

i parsing csv multiple columns. number of columns not fixed in csv file. varies 5 10. need recreate data.frame these columns inside function. wondering if there multiple arguments functionality in r 1 in ruby(*args). if not, how achieve this??? searched bit , found if have col name as

col1 col2 

i can use:

list <- ls(pat="^col\\d$") 

and pass list argument function, pass column names, characters, not values these column names carrying.

any suggestions????

edit: parsing file ror app , using rinruby gem call r functions. parsing csv ruby , passing individual column contents single variable in r. in r, need create data.frame. not data frame originally. in method cal_norm below assigning variables in r using loop names col1, col2, col3....and on.

here rails code:

 class uploadscontroller < applicationcontroller    attr_accessor :calib_data, :calib_data_transpose, :inten_data, :pr_list    def index     @uploads = upload.all      @upload = upload.new    respond_to |format|   format.html    format.json { render json: @uploads }      end  end   def create   @upload = upload.new(params[:upload])    directory = "public/"  io_calib = params[:upload][:calib]  io_inten = params[:upload][:inten]      name_calib = io_calib.original_filename  name_inten = io_inten.original_filename  calib_path = file.join(directory, "calibs", name_calib)  inten_path = file.join(directory, "intens", name_inten)  respond_to |format|   if @upload.save     @calib_data, @calib_data_transpose = import(calib_path)     @inten_data = import_ori(inten_path)     #probe list of uploaded file     @probe_list = calib_data_transpose[0]     logger.debug @probe_list.to_s     flash[:notice] = "files uploaded!!"     format.html     #format.js #{ render json: @upload, status: :created, location: @upload }   else     flash[:notice] = "error in uploading!!"     format.html { render action: "index" }     format.json { render json: @upload.errors, status: :unprocessable_entity }     end   end  end  def cal_norm    #ajax request    data = params['data'].split(',')     in 0..@calib_data_transpose.length - 1   r.assign "col#{i}", @calib_data_transpose[i]    end    r.assign "cells", @inten_data   r.assign "pr", data   r.eval <<-eof  # make sure convert them in character , numeric vectors  #match selected pr in table  #convert found row of values data.frame numeric  #divide each column of table respective pr values , create new table repat different pr.  #make new table ce count , different probe normalization , calculate  individual pr  #finally return data.frame pr names , cell counts  #return individual columns array not in form of matrix/data.frame  eof  end  def import(file_path)   array = import_ori(file_path)   array_splitted = array.map {|a| a.split(",")}    array_transpose = array_splitted.transpose   return array_splitted, array_transpose end   def import_ori(file_path)   string = io.read(file_path)   array = string.split("\n")   array.shift   return array  end  end 

post updated question:

i utter newbie of ruby found example here: col wise data

here column wise data read col_data, 0 here (col) index (no ruby testing :( )

require 'csv' col_data = [] csv.foreach(filename) {|row| col_data << row[0]} 

assign col data variables col1...coln, , create counter number of columns (syntax might not 100% correct)

for in 0..@calib_data_transpose.length - 1  #r.assign "col#{i}", @calib_data_transpose[i]   csv.foreach(filename) {|row| "col#{i}" << row[i]} end  r.col_count=@calib_data_transpose.length - 1 

and once col1..coln created, combine column data 1 index @ time starting @ = 1. result data.frame order of columns col1.... coln.

r.eval <<-eof  for(i in 1:col_count) {    if (i==1) {     df<-data.frame(get(paste0("col",i)))    }    else {     df<-cbind(df,get(paste0("col",i)))   }    names(df)[i]<-paste0("col",i) }  eof 

let know if helps...

---

not relevant updated question anymore retaining posterity.

subset data.frame given pattern

as roland stated above read.csv read entire file, since wish control columns retained in data.frame following:

using data(mtcars) sample data.frame

code:

read in data:

> data(mtcars) > head(mtcars)                    mpg cyl disp  hp drat    wt  qsec vs gear carb mazda rx4         21.0   6  160 110 3.90 2.620 16.46  0  1    4    4 mazda rx4 wag     21.0   6  160 110 3.90 2.875 17.02  0  1    4    4 datsun 710        22.8   4  108  93 3.85 2.320 18.61  1  1    4    1 hornet 4 drive    21.4   6  258 110 3.08 3.215 19.44  1  0    3    1 hornet sportabout 18.7   8  360 175 3.15 3.440 17.02  0  0    3    2 valiant           18.1   6  225 105 2.76 3.460 20.22  1  0    3    1 

subset data condition, columns beginning alphabet 'c'

> head(mtcars[,grep("^c",colnames(mtcars))])                    cyl carb mazda rx4           6    4 mazda rx4 wag       6    4 datsun 710          4    1 hornet 4 drive      6    1 hornet sportabout   8    2 valiant             6    1 

here '^c' similar pattern pat="^col\\d$" question. substitute '^c' regular expression of choice e.g '^col'.the '^c' match pattern beginning alphabet 'c', match @ end of string use '$c'