ruby,file,csv,dir , Saying there are 0 arguments when I have 2? Trying to open a CSV file to write into

## Question:

Tag: ruby,file,csv,dir

I'm trying to read from a CSV file and codify people into groups using an equation. I append the name of their group they fall into to the end of the array that their row creates. Then I write it to a new file so I don't overwrite the original file in case something goes wrong.

Also, it loops through the directory and does this for multiple csv files.

However, when I try to open the new file to write into, it's saying this:

Segmenter.rb:12:in open': wrong number of arguments (0 for 1) (ArgumentError)
from Segmenter.rb:12:in foreach'
from Segmenter.rb:12:in <main>'


Here is the script with the coefficients removed. All the x's in the coefficients array are numbers in my script.

require 'csv'

coefficients = [
[x, x, x, x, x, x, x, x, x, "Utilitarians"],
[x, x, x, x, x, x, x, x, x, "Hometown School/Social"],
[x, x, x, x, x, x, x, x, x, "State Pride"],
[x, x, x, x, x, x, x, x, x, "Hard-Wired Advocates"],
[x, x, x, x, x, x, x, x, x, "Game Hunters"]
]

Dir.foreach do |current_file|

data_set.array.each do |row|
segment_value = 0
segment_name = ""
coefficients.each do |segment|
if (segment[0] *  row[1] + segment[1]*row[2] + segment[2]*row[3] + segment[3]*row[4] + segment[4]*row[5] + segment[5]*row[6] + segment[6]*row[7] + segment[7]*row[8]) > segment_value
segment_value = segment[0] *  row[1] + segment[1]*row[2] + segment[2]*row[3] + segment[3]*row[4] + segment[4]*row[5] + segment[5]*row[6] + segment[6]*row[7] + segment[7]*row[8]
segment_name = segment[8]
end
row << segment_name
end

CSV.open("#{current_file.basename} SEGMENTED.csv", "w") do |writer|
data_set.array.each do |data|
writer << data
end
end

end

end


I believe the problem is with Dir.foreach, not CSV.open.

You need to supply a directory to foreach as an argument. That's why you are getting the missing argument error.

Try:

Dir.foreach('/path/to_my/directory') do |current_file|

I think the open that is referenced in the error message is when Dir is trying to find the directory to open in order to get the file list for foreach`.

# Related:

## RSpec test for rake task

I have created a custom rake task that deletes all items that are >= 7 days old. I am trying to write a RSpec test for this new task but it seems like my task isn't really running in the test. I have tested the task manually and it works...

## Ruby gsub group parameters do not work when preceded by escaped slashes

ruby,regex
I am trying to perform a trivial substitution, that in any other language I have come across, work as per the documentation. However, my substitution fails for some reason. The documentation examples list: "hello".gsub(/[aeiou]/, '*') #=> "h*ll*" "hello".gsub(/([aeiou])/, '<\1>') #=> "h<e>ll<o>" "hello".gsub(/./) {|s| s.ord.to_s + ' '} #=> "104 101...

## Rust: Lifetime of String from file [duplicate]

file,io,rust
This question already has an answer here: Return local String as slice 1 answer I'm trying to read in some external GLSL code into Rust. The reading works properly, but I run into a lifetime issue in the final expression (in the Ok(_) branch) error: s does not live...

## Heroku RAM not increasing with upgraded dynos

ruby-on-rails,ruby,ruby-on-rails-3,memory,heroku
I have a massive function i have been calling manually through the heroku rails console. I have been receiving the error rapid fire in my logs: 2015-06-22T14:56:42.940517+00:00 heroku[run.9877]: Process running mem=575M(112.4%) 2015-06-22T14:56:42.940517+00:00 heroku[run.9877]: Error R14 (Memory quota exceeded) A 1X dyno is suppose to have 512 MB of RAM. I...

## Storing columns on disk and reading rows

c++,file,matrix,io
So I have a C++ code that finds the inverse of a square matrix. The inverse is full and it would be bad to keep it all in memory because I am working with hundreds of thousands of columns. My code generates the columns one by one. After finding the...

## Ruby boolean logic: some amount of variables are true

ruby
Let say I have 3 variables: a, b, c. How can I check that just zero or one of them is true?...

## What is Rack::Utils.multipart_part_limit within Rails and what function does it perform?

ruby-on-rails,ruby,rack,multipart
Rack::Utils.multipart_part_limit is set to 128 by default. What purpose does the value have and what effect does it have within the Rails system?...

## How to get return value from a forked / spawned process in Ruby?

ruby,process,output,fork,spawn
My simple test program: pid = Process.spawn("sleep 10;date") How can I place the output (eg stdout) of the "date" command in a variable when it is available? I don't want to use a file for the data exchange....

## Ruby access words in string

ruby
I don't understand the best method to access a certain word by it's number in a string. I tried using [] to access a word but instead it returns letter. puts s # => I went for a walk puts s[3] # => w ...

## On rendering from controller, current_page method does not seem to work

ruby-on-rails,ruby,ruby-on-rails-4,model-view-controller
I have a navigation bar included in application.html.erb. Because for some pages, such as the signup page, I need to place additional code inside the navigation bar, I have excluded those pages for showing the navigation bar through application.html.erb and instead included it in their respective view pages. See code...

## Keep leading zeroes when converting string to integer

ruby
For no particular reason, I am trying to add a #reverse method to the Integer class: class Integer def reverse self.to_s.reverse.to_i end end puts 1337.reverse # => 7331 puts 1000.reverse # => 1 This works fine except for numbers ending in a 0, as shown when 1000.reverse returns 1 rather...

## IllegalStateException: Iterator already obtained [duplicate]

java,file,loops,path
This question already has an answer here: java.lang.IllegalStateException: Iterator already obtained 1 answer so I wrote a little Java program to test a little stack language I made vie various test file, but for some reason it won't work. Here is the code: import org.apache.commons.io.FilenameUtils; import java.io.IOException; import java.nio.file.*;...

ruby-on-rails,ruby,rest,activerecord,one-to-many
I'm creating a rails application that is a backend for a mobile application. The backend is implemented with a RESTful web API. Currently I am trying to add gamification to the platform through the use of badges that can be earned by the user. Right now the badges are tied...

## Same enum values for multiple columns

ruby-on-rails,ruby,enums
I need to do something like this: class PlanetEdge < ActiveRecord::Base enum :first_planet [ :earth, :mars, :jupiter] enum :second_planet [ :earth, :mars, :jupiter] end Where my table is a table of edges but each vertex is an integer. However, it seems the abvove is not possible in rails. What might...

## Ruby: How to copy the multidimensional array in new array?

ruby-on-rails,arrays,ruby,multidimensional-array
seating_arrangement [ [:first, :second, :none], [:first, :none, :second], [:second, :second, :first], ] I need to copy this array into new array. I tried to do it by following code: class Simulator @@current_state def initialize(seating_arrangement) @@current_state = seating_arrangement.dup end But whenever I am making any changes to seating_arrangement current_state changes automatically....

## How to get rid of .ignore file in Git?

git,file,bitbucket,ignore
I have create an ignore file , the list included .jar files . I then merged my branch to a development branch and even though I had resolved all my conflicts , I still had a lot of errors. Most of them had something to do with support.v4 (the import...

## Get the actual value of a boolean attribute

ruby,page-object-gem,rspec3,rspec-expectations
I have the span: <span disabled="disabled">Edit Member</span> When I try to get the value of the disabled attribute: page.in_iframe(:id => 'MembersAreaFrame') do |frame| expect(page.span_element(:xpath => "//span[text()='Edit Member']", :frame => frame).attribute('disabled')).to eq("disabled") end I get: expected: "disabled" got: "true" How do I get the value of specified attribute instead of a...

## How to pivot array into another array in Ruby

arrays,ruby,csv
I have a multidimensional array like this one : myArray = [["Alaska","Rain","3"],["Alaska","Snow","4"],["Alabama","Snow","2"],["Alabama","Hail","1"]] I would like to end up with CSV output like this. State,Snow,Rain,Hail Alaska,4,3,nil Alabama,2,nil,1 I know that to get this outputted to CSV the way I want it I have to have output array like this: outputArray =[["State","Snow","Rain","Hail"],["Alaska",4,3,nil],["Alabama",2,nil,1]]...

## Appending an element to a page in VoltRb

html,ruby,opalrb,voltrb
I'm trying to append an element to one of my pages in a Volt project, via opal-browser, like so: if RUBY_PLATFORM == 'opal' require 'browser' \$document.body << my_dom_element.to_n end # controller code below Unfortunately, I'm getting an error: [Error] TypeError: null is not an object (evaluating 'value.nodeType') (anonymous function) (main.js,...

## Ruby- get a xml node value

ruby,xml
can someone help me in extracting the node value for the element "Name". Type 1: I am able to extract the "name" value for the below xml by using the below code <Element> <Details> <ID>20367</ID> <Name>Ram</Name> <Name>Sam</Name> </Details> </Element> doc = Nokogiri::XML(response.body) values = doc.xpath('//Name').map{ |node| node.text}.join ',' puts values...

## How to handle backslash “\” escape characters in q string and heredocument

ruby
Ruby Newbie here. I do not understand why Ruby looks inside %q and escapes the \. I am using Ruby to generate Latex code. I need to generate \\\hline which is used in Latex for table making. I found \\\hline as input generated \hline even though the string was inside...

## Split an array into slices, with groupings

arrays,ruby,enumerable
I've got some Ruby code here, that works, but I'm certain I'm not doing it as efficiently as I can. I have an Array of Objects, along this line: [ { name: "foo1", location: "new york" }, { name: "foo2", location: "new york" }, { name: "foo3", location: "new york"...