The error I got:
rake 1:1 solved=true
ruby -c '/Users/wim/Projects/ruby-kickstart/session1/solved/1.rb'
ruby: No such file or directory -- /Users/wim/Projects/ruby-kickstart/session1/solved/1.rb (LoadError)
rake aborted!

Directory name is "solved" should be "5-solved", after I changed it, it worked fine. It is on line 64 of the Makefile.

While running bundle install, nokogiri installation fails leading to your PC blowing up.

Simple fix - as provided by nokogiri - try this in terminal...

sudo apt-get install ruby-dev zlib1g-dev liblzma-dev

then run you bundle install again.

http://www.nokogiri.org/tutorials/installing_nokogiri.html#ubuntu___debian

I'm not sure on how to make my change noticeable to you guys. but please have a look at my commit
https://github.com/AlexAvlonitis/ruby-kickstart/commit/613644a6f2def2b92a7557a07cb165ce0e4b224d

Anyone who's done/looked at 2.13 able to offer some explanation for the use of self.var over @var in the last question? They both pass tests and so seem to be functionally identical and so I wanted to see if there was a reason why the author used self.var in this case or was it just a stylistic choice.

Here are a few links to explanations of the differences between self.var and @var:

http://stackoverflow.com/questions/12097726/ruby-classes-initialize-self-vs-variable
http://stackoverflow.com/questions/1693243/instance-variable-self-vs
http://stackoverflow.com/questions/5275749/ruby-should-i-use-self-or

Any thoughts let me know :)

class User
  attr_accessor:username, :blogs

  def initialize(username)
    @username = username
    @blogs = []
  end

  def add_blog(date, text)
    added_blog = Blog.new(date, @username, text)
    blogs << added_blog
    @blogs = blogs.sort_by { |blog| blog.date }.reverse
    added_blog
  end

end

class Blog

  attr_accessor :date, :user, :text

  def initialize(date, user, text)
    @date = date
    @user = user
    @text = text
  end

   def summary
    text.split[0..9].join(' ')
  end

  def entry
    "#{user.username} #{date}\n#{text}"
  end

  def ==(other)
    date   == other.date &&
      user == other.user &&
      text == other.text
  end
end

vs

require 'date'

class User
  attr_accessor :username, :blogs

  def initialize(username)
    self.username = username
    self.blogs    = []
  end

  def add_blog(date, text)
    added_blog = Blog.new(date, self, text)
    blogs << added_blog
    self.blogs = blogs.sort_by { |blog| blog.date }.reverse
    added_blog
  end
end



class Blog
  attr_accessor :date, :user, :text

  def initialize(date, user, text)
    self.date = date
    self.user = user
    self.text = text
  end

  def summary
    text.split[0..9].join(' ')
  end

  def entry
    "#{user.username} #{date}\n#{text}"
  end

  def ==(other)
    date   == other.date &&
      user == other.user &&
      text == other.text
  end
end

I've noticed I have got this error with my pull request. I'm not sure what it means..

https://travis-ci.org/makersacademy/ruby-kickstart/builds/96808466

Can anyone shed any light?

This is my code:

def sum_difference_product
a = gets.to_i
b = gets.to_i
puts a + b
puts a - b
puts a * b
end

this is the solution...

def sum_difference_product
a , b = gets.split.map { |num| num.to_i }
puts a + b
puts a - b
puts a * b
end

am I not getting the solution? is it just because there is one input in the solution and I have two. I just feel I get to the same result.

I am having an issue with Travis - it seems to be showing a build failure message for session 2 exercises when I have only pushed up session 1 exercises, which are shown to be passing.

https://travis-ci.org/makersacademy/ruby-kickstart/builds/237880081?utm_source=github_status&utm_medium=notification

Hi guys,

the way I was trying to solve the 2.3 challenge has reached its' limits. Here's the code I've been using

class String
  def every_other_char
    arrays = self.split("").each_slice(2).to_a
    arrays.each do |array|
    array.pop
  end
  arrays.join
  end
end

And here' the error message

 1) String#every_other_char "Four score and seven years ago..." -> "Fu cr n ee er g.."
     Failure/Error: expect(input.every_other_char).to eq output

       expected: "Fu cr n ee er g.."
            got: "Fu cr n ee er g."

Now I know why what's causing the error, just not how to fix it.

I'm splitting the array into sub arrays of 2, but the last sub array has only one element in it. So I end up with something like this [[......] , [[ . ] , [ . ] ] , [ . ]]

So when the program reaches the dots it pops out the last dot in the second to last sub-array, and reaches the end and pops out the last sub array. This means I'm returning one dot instead of two.

I know this is quite convoluted, but I hope it makes sense.

My issue is can this challenge be solved this way at all? I'm not sure how to circumvent the odd number of elements issue. Does anyone know how to solve this?

Thanks!!

Hi @nikeshashar - In spite of the obvious cleaner code state of the solved solution provided (commented out below) why is my code not passing all the test-cases of Rake 1:4? At first glance I thought it was test-case with 0 values, but then I fixed it. So, honestly, no idea why my code fails running through all examples on Rakefile. After a while I decided to look at the solution, but still that didn't provide me with any insight...

# A grad student at a local university thinks he has discovered a formula to
# predict what kind of grades a person will get. He says if you own less than
#10 books, you will get a "D". If you own 10 to 20 books, you will get a "C",
# and if you own more than 20 books, you will get a "B".
# He further hypothesizes that if you actually read your books, then you will
# get a full letter grade higher in every case.
#
# grade(4,  false)  # => "D"
# grade(4,  true)   # => "C"
# grade(15, true)   # => "B"

# <10 books => D, 10..20 books => C, >20 book =>B


def grade(num_books, has_read_books)
  ##SOLUTION## 
 # if has_read_books
  #   return "C" if num_books <  10
  #   return "B" if num_books <= 20
  #   return "A"
  # else
  #   return "D" if num_books <  10
  #   return "C" if num_books <= 20
  #   return "B"
  # end

   if num_books == 0
       print "D"
   elsif num_books > 0 && num_books < 10 && has_read_books == "true"
      print "C"
   elsif num_books > 0 && num_books < 10 && has_read_books == "false"
     print "C".next
   elsif num_books >= 10 && num_books < 20 && has_read_books == "true"
     print "B"
   elsif num_books >= 10 && num_books < 20 && has_read_books == "false"
     print "B".next
   elsif num_books >= 20 && has_read_books == "true"
     print "A"
   elsif num_books >= 20 && has_read_books == "false"
     print "A".next
    end
end

#grade 5, "true"

Thank you very much in advance!

This is the code I have written for Challenge 4. I can't seem to get it to work as the error message I get back from the rake is 1) grade for non book reader returns "D" when given 0 books
Failure/Error: expect(grade num_books, false).to eq "D"
ArgumentError:
bad value for range
# ./session1/3-challenge/4_logic.rb:23:in grade' # ./session1/4-spec/4.rb:5:inblock (4 levels) in <top (required)>'

The code I am using is:

def grade(num_books, has_read_books)
if num_books < 10 && has_read_books
puts "C"
else
puts "D"
end

if num_books 10..20 && has_read_books
puts "B"
else
puts "C"
end

if num_books > 20 && has_read_books
puts "A"
else
puts "B"
end
end

Any ideas?

So, I was trying to take inspiration from 1:6 as it seemed to be asking for the same sort of actions, but I just keep getting the same error and I'm not sure how to fix it.

The error is:

1. String#every_other_char "" -> ""
   Failure/Error: expect("".every_other_char).to eq ""

 NoMethodError:
   undefined method `each_index' for "":String
 # ./session2/3-challenge/3_array.rb:10:in `every_other_char'
 # ./session2/4-spec/3.rb:3:in `block (2 levels) in <top (required)>'

And my code is:

class String
def every_other_char
self.split(",").values_at(* self.each_index.select {|i| i.even?}).join('')
end
end

As the title mentions, the solution is already given.

Hi everyone,

Travis CI doesn't like my answers, as i see others experiencing the same issue. when i run rake 1:1 locally it's fine without errors. but when i make a pull request, CI finds errors that i can't understand.
log: https://travis-ci.org/makersacademy/ruby-kickstart/builds/96735486

thanks

After spending the whole day on this problem, this is the best idea I could come up with:

def pirates_say_arrrrrrrrr(string)

string.split("").each do|ch|
 if ch == /r/i
    puts ch[+1]
 end
end

end

Can any one help me, please?

I have had a look over this and can't figure out where it is going wrong. The first test for arguements (1, 2) comes back 0

def arithmetic2(a, b)
if a < b
return (a / 2).to_f
else
return (b / 2).to_f
end
end

Ok gang, my turn please.

My lowest method is behaving oddly. When i call it separately to the initialize method in two steps it behaves as expected:

f = Fraction.new(20,60)
f.lowest
f.numerator # => 1
f.denominator # => 3

When the methods are concatenated it seems to reverse the numerator and denominator values for some arcane reason:

f = Fraction.new(20,60).lowest
f.numerator # => 3
f.denominator # => 1

Any sage advice would be greatly appreciated. Full code for the exercise is as follows:

class Fraction
  attr_accessor 'numerator', 'denominator'

  def initialize(numerator, denominator)
    @numerator = numerator
    @denominator = denominator
  end

  def gcd(a,b)
    return a if b == 0
    gcd(b, a%b)
  end

  def lowest
    lowest = gcd(@numerator, @denominator)
    @numerator /= lowest
    @denominator /= lowest
  end

  def to_f
    @numerator.to_f / @denominator.to_f
  end

  def to_s
    "#{@numerator}/#{@denominator}"
  end

end

When I try to test my code with rake it keeps telling me my code is incorrect. I have tried copying the code from the solved folder and it's still not working so the problem is clearly not my code. It doesn't happen with every challenge, just a few of them. Also, most of the time rake rejects my code irb says it's fine (not always though). Does anyone have any idea what the problem could be? Please help as I can't keep working on the challenges until this is fixed :-(

Hey,

I think that my rake won't run because my rspec is too advanced.

Gem::LoadError: Could not find 'rspec' (~> 3.2.0) - did find: [rspec-3.4.0]
Checked in 'GEM_PATH=/Users/Viola/.rvm/gems/ruby-2.2.1:/Users/Viola/.rvm/gems/ruby-2.2.1@global', execute gem env for more information

So I edited the version of rspec at the top of the Rakefile to 3.4.0 (from 3.2.0)

I tried running 'rake 1.1' and this is what I got:

(in /Users/Viola/Desktop/Programming/MakersAcademy/Pre-Course/Week2/ruby-kickstart)
rake aborted!
SyntaxError: /Users/Viola/Desktop/Programming/MakersAcademy/Pre-Course/Week2/ruby-kickstart/Rakefile:13: syntax error, unexpected ':', expecting end-of-input
session2 , prb2 = t2.name.split ':'
^
/Users/Viola/.rvm/gems/ruby-2.2.1/bin/ruby_executable_hooks:15:in eval' /Users/Viola/.rvm/gems/ruby-2.2.1/bin/ruby_executable_hooks:15:in

Which means there's an error on line 13...

I've been chasing around the internet for a while now, any help most welcome.

@nikeshashar

I slightly changed the second file of Session 2, and added it to the pull request.

Will this create problems when testing the files? Both passed Rake 2:2

hey everyone, i'm trying to break down 2:12 and try to understand from the solution and instructions provided because i couldn't solve it myself, even if i copy the ready solution, the results are not the same as the example...
the example says:

lissa = User.new 'QTSort'

lissa.username # => "QTSort"

lissa.blogs # => []

lissa.add_blog Date.parse("2010-05-28") , "Sailor Mars is my favourite"

lissa.blogs # => [ blog1 ]

Blog.new Date.parse("2007-01-02"), lissa, "Going dancing!" # we'll call this blog2

Blog.new Date.parse("2006-01-02"), lissa, "For the last time, fuck facebook >.<" # we'll call this blog3

Blog.new Date.parse("2010-01-02"), lissa, "Got a new job, cuz I'm pretty much the best ^_^" # we'll call this blog4

lissa.blogs # => [ blog1 , blog4 , blog2 , blog3 ]

when I did it on my computer with the solution provided, the last lissa.blogs call still shows 1 blog,
I can't see how
Blog.new Date.parse("2007-01-02"), lissa, "Going dancing!"
will save the newly created blog in the User class under blogs array. Hope you understand...

Below is task 6 from session 2. My answer is written underneath - it doesn't pass all tests, and I can't seem to figure out why.

Anyone know why this doesn't fully pass? What is wrong with my logic here?

Thanks!!

Hi @nikeshashar - so, running Rake 1:5 does not fully validate my answer when all the 3 cases provided in the example comments I get them correctly. In all honesty, after several hours fighting, I also couldn't grasp the comments of the failures either (Screenshot provided).. So, which test-cases am I missing with my code below:

# Given a string, replace every instance of sad to happy
#
# add_more_ruby("The clowns were sad.")         # => "The clowns were happy."
# add_more_ruby("The sad dad said sad stuff.")  # => "The happy dad said happy stuff."
# add_more_ruby("Sad times are ahead!")         # => "Happy times are ahead!"

def add_more_ruby(string)
  string.gsub!(/sad/i, 'happy')
  print string.capitalize
  #string.gsub('sad', 'happy').gsub('Sad', 'Happy')  # => Solved code that does validate Rake 1:5  
end

Thank you in advance!!

I'm feeling very stuck, especially as the user AlexAvlontis who posted an issue about this challenge seemed to have a completely different challenge to the one I'm working on.

Anyway, my code keeps blowing up here:

def lowest
    puts "lowest method is running"
    puts "Calculating numerator gcd"
    @numerator = self.gcd @numerator, @denominator
    puts "Numerator gcd calculation complete"
    puts @numerator # => produces a blank line
    puts "Calculating denominator gcd"
    @denominator = self.gcd @denominator, @numerator 
    puts "Denominator calculation complete"
    puts "lowest method is complete"
    return @numerator, @denominator
end

def gcd(a,b) => # => Running from: puts "Calculating denominator gcd" : @denominator = self.gcd @denominator, @numerator 
    puts "gcd method is running"     
    return a if b == 0
    self.gcd(b, a%b) # => Throws the error: `%': nil can't be coerced into Float (TypeError)
    puts "gcd method is complete"
  end

I think I've misunderstood how fractions work, but it seems that the @numerator variable being passed to the gcd methods "b" parameter has nothng in it... which on further testing is indeed the case, as calling "puts" on it produces a blank line. Let me go and revise basic mathematics, but can anyone shed light on why @numerator is being calculated to an empty variable by the code I'm currently using?

As part of 2:7 I'm trying to select alternate words in an array like this:

def alternate_words sentence
sentence_array = sentence.split
sentence_array.select! { |x| sentence_array.index(x).even? }
sentence_array
end

This works most of the time, except for the longest test:

p alternate_words "I could have made money this way, and perhaps amused myself writing code. But I knew that at the end of my career, I would look back on years of building walls to divide people, and feel I had spent my life making the world a worse place."

which gives the odd word that shouldn't be there:

["I", "have", "money", "way,", "perhaps", "myself", "code.", "I", "that", "the", "of", "career,", "I", "would", "back", "years", "of", "building", "to", "people,", "feel", "I", "had", "my", "making", "world", "worse"]

Any ideas what I've done wrong here?

Hi, I have completed the code for this challenge, and every example I pass to it, it seems to work, yet it fails the rake test and I can not interpret the reason. Any ideas? Thanks.

def alternate_words(sentence)
    arr = sentence.split
    new_arr = []
    arr.map.with_index { |value, index| new_arr << value if index.even? }
    new_arr = new_arr.map { |element| element.tr("!@$#%^&*()-=_+[]:;,./<>?\|", '') }
end

I know there is probably a prettier way to do this but I'm still not sure why this doesn't work.

def grade(num_books, has_read_books)

if num_books < 10 && has_read_books != true
"D"
elsif num_books <= 10 && has_read_books == true
"C"
elsif num_books (10..20) && has_read_books != true
"C"
elsif num_books (10..20) && has_read_books == true
"B"
elsif num_books > 20 && has_read_books != true
"B"
else
num_books > 20 && has_read_books != true
"A"
end

end

Hi,

When I try to push to git hub, I keep getting this error. Any ideas why?

Cheers

Dan

Just to make you aware that you call it 'rack' in the readme, but the challenge files do correctly instruct the user to use rake #:#

EDIT: Unless of course it is meant to be rack, which I've never heard of.

Hi guys,

I forked the repo and cloned it locally but something wrong with bundle install.

valentina@osboxes:$ bundle install
The program 'bundle' is currently not installed. To run 'bundle' please ask your administrator to install the package 'bundler'
valentina@osboxes:$ gem install bundler
Fetching: bundler-1.11.0.gem (100%)
ERROR: While executing gem ... (Gem::FilePermissionError)
You don't have write permissions for the /var/lib/gems/2.1.0 directory.
valentina@osboxes:~$ sudo gem install bundler
[sudo] password for valentina:
Fetching: bundler-1.11.0.gem (100%)
Successfully installed bundler-1.11.0
Parsing documentation for bundler-1.11.0
Installing ri documentation for bundler-1.11.0
Done installing documentation for bundler after 6 seconds
1 gem installed

valentina@osboxes:$ cd ruby-kickstart/
valentina@osboxes:/ruby-kickstart$ bundle install
Fetching gem metadata from https://rubygems.org/.........
Fetching version metadata from https://rubygems.org/..
Resolving dependencies...
Using rake 10.4.2
Installing mime-types 2.4.3
Installing mini_portile 0.6.2
Installing rack 1.6.0
Using diff-lcs 1.2.5
Installing helloworld 0.0.1
Installing rspec-support 3.2.2 (was 3.1.2)
Installing tilt 1.4.1
Using bundler 1.11.0
Installing nokogiri 1.6.6.2 with native extensions

Gem::Ext::BuildError: ERROR: Failed to build gem native extension.

/usr/bin/ruby2.1 extconf.rb

mkmf.rb can't find header files for ruby at /usr/lib/ruby/include/ruby.h

extconf failed, exit code 1

Gem files will remain installed in /tmp/bundler20151214-3156-1eqy0venokogiri-1.6.6.2/gems/nokogiri-1.6.6.2 for inspection.
Results logged to /tmp/bundler20151214-3156-1eqy0venokogiri-1.6.6.2/extensions/x86_64-linux/2.1.0/nokogiri-1.6.6.2/gem_make.out
Installing rack-test 0.6.3
Installing rack-protection 1.5.3
Installing rspec-core 3.2.3 (was 3.1.7)
Installing rspec-expectations 3.2.1 (was 3.1.2)
Installing rspec-mocks 3.2.1 (was 3.1.3)
An error occurred while installing nokogiri (1.6.6.2), and Bundler cannot
continue.
Make sure that gem install nokogiri -v '1.6.6.2' succeeds before bundling.

Anyone knows what's wrong? I'm using UBUNTU

FYI @spike01 - as I went through forking the repo and attempting some of the exercises... I realized that original repo (i.e. Josh Creek's one) contains a few more cheat sheets that are key for the initial sections. Particularly these are:
arrays
logic and control
hashes
strings

See snapshot below to compare:

Hi guys. I have installed rspec 3.2.0 and bundle. When I run rake 1:1 I get this error:

Does anybody knows how could I fix this?

Hi there I'm stack on this one, this is what I got

'def pirates_say_arrrrrrrrr(string)
final_world = ""
string.length.to_i.times {|x| final_string << string[x+1] if string[char] == 'r' || string[char] == 'R'}
end
'
rspec ./session1/4-spec/7.rb:2 # pirates_say_arrrrrrrrr returns "eeu" when given "are you really learning Ruby?"

Thanks