Another noob question

Thanks to everyone that helped me a few days ago. This time I am trying
to write a program that incorporates everything that I have learned in
the last week but I am more than sure that I am making mistakes
somewhere. Also there is somethings I do not know how to do.
Everything is commented so it should be easy to find. Also if anyone
has any suggestions about my syntax style please give me advice. Thanks
again everyone!


Program written by Dr. Omar Israel Velez

This program will try to integrate several concepts that I have

learned so far

The program will ask for some basic information and then it will ask

for a

list of favorite books. Afterwards it will sum up the total number of

characters in the book titles and add how many of each letter there

are.

finally it will offer a new book as a suggestion based on which letter

was the

most popular.

puts “What\s your first name?” ; first_name = gets.chomp ; puts
puts “What’s your last name?” ; last_name = gets.chomp ; puts

puts “Well, #{first_name} #{last_name}, tell me four books that you have
read:”
puts
books_one = gets.chomp ; books_two = gets.chomp
books_three = gets.chomp ; books_four = gets.chomp

all_books = ["#{books_one.downcase}", “#{books_two.downcase}”,
“#{books_three.downcase}”, “#{books_four.downcase}”].sort

Is there a more efficient way to write this code where I don’t have to

isolate each one and I can downcase everything at once?

puts

puts “These are the books that you entered #{first_name}.” ; puts

all_books.each do |books|
puts books
end

puts

puts “#{first_name} are these books correct?” ; answer = gets.chomp ;
puts

if answer == ‘yes’
puts “Ah, very good choice of books #{first_name}.”
else
puts “Well computers never make mistakes so it must be in your head.”
puts “Run the program again please.”
end

puts

a = books_one.length ; b = books_two.length
c = books_three.length ; d = books_four.length

Same question as before, can I .length everything at the same time

and make

the code more efficient?

total_characters = a + b + c + d

I cheated and just went with the total number of characters. But how

do I

add up the total number of each letter and then suggest a book for

each letter?

just two or three examples will be ok I know asking for 26 examples

is just crazy.

puts “There are #{total_characters} total characters in the tittles you
read.”
puts

if total_characters >= 50
puts “I recommend reading The Hobbit.”
puts “There is a #{rand(101)}% chance you will like this book.”
puts “Would you like to read this book?” ; answer = gets.chomp ; puts
if answer == ‘yes’
puts “I am sure that you will enjoy it #{first_name}”
else
puts “Oh that is too bad, how about Animal Farm then?”
puts “There is a #{rand(101)}% chance you will like this book.”
end
else
puts “I recommend you read The Tale of Two Cities.”
puts “There is a #{rand(101)}% chance you will like this book.”
puts “Would you like to read this book #{first_name}?” ; answer =
gets.chomp
puts
if answer == ‘yes’
puts “I am sure that you will have a great time reading it!”
else
puts “Ok then, how about A Day in the Life of Alex Jones?”
puts “There is a #{rand(101)}% chance you will like this book.”
end
end

I also tried to create a global constant like so…

percent = “There is a #{rand(101)}% chance you will like this book.”

and then point to it to make the code look cleaner but it would not

let me.

How would I do this?

On Mon, Mar 29, 2010 at 4:55 PM, Omar V. [email protected]
wrote:

Program written by Dr. Omar Israel Velez

most popular.

puts “What\s your first name?” ; first_name = gets.chomp ; puts
puts “What's your last name?” ; last_name = gets.chomp ; puts

puts “Well, #{first_name} #{last_name}, tell me four books that you have
read:”
puts

> books_one = gets.chomp ; books_two = gets.chomp

> books_three = gets.chomp ; books_four = gets.chomp

> all_books = [“#{books_one.downcase}”, “#{books_two.downcase}”,

> “#{books_three.downcase}”, “#{books_four.downcase}”].sort

all_books = []
4.times do
all_books << gets.chomp.downcase
end

all_books.sort!

Is there a more efficient way to write this code where I don’t have to

isolate each one and I can downcase everything at once?

puts

puts “These are the books that you entered #{first_name}.” ; puts

> all_books.each do |books|

> puts books

> end

puts books

puts “Run the program again please.”
exit

end

puts

> a = books_one.length ; b = books_two.length

> c = books_three.length ; d = books_four.length

Same question as before, can I .length everything at the same time

and make

the code more efficient?

> total_characters = a + b + c + d

total_characters = all_books.inject(0) {|total, book| total +
book.length}

I cheated and just went with the total number of characters. But how

do I

add up the total number of each letter and then suggest a book for

each letter?

just two or three examples will be ok I know asking for 26 examples

is just crazy.

The letter histogram

h = Hash.new(0)
all_books.each {|b| b.split(//).each {|letter| h[letter] += 1}}

If you want to suggest a book for each letter, you’ll have to have a
list of books by letter. Something like:

recommendations = {‘a’ => “A whatever”, ‘b’ => “because…”} # Crazy !
I didn’t come up with any book title !!! (I’m not a native speaker)

Then you can recommend based on the present letters, if I understood
correctly:

h.keys.each {|initial| puts “I recommend: #{recommendations[initial]}”}

else
puts “I am sure that you will have a great time reading it!”
else
puts “Ok then, how about A Day in the Life of Alex Jones?”
puts “There is a #{rand(101)}% chance you will like this book.”
end
end

Whenever you see duplicated code, that’s a good place to refactor:

def recommend(name, books)
books.each do |book|
puts “I recommend you read #{book}”
puts “There’s a #{rand(101)}% chance you’ll like it”
puts “Would you like to read this book #{name}?”
answer = gets.chomp
if answer == “yes”
puts “I’m sure you’ll like it”
break
end
end
end

or something like that, then:

if total_characters < 50
recommend(first_name, [“The Hobbit”, “Animal Farm”])
else
recommend(first_name, [“The Tale of Two Cities”, “A Day in the Life
of Alex Jones”])
end

Well, this is not exactly equivalent to your code, but you get the idea.

I also tried to create a global constant like so…

percent = “There is a #{rand(101)}% chance you will like this book.”

and then point to it to make the code look cleaner but it would not

let me.

How would I do this?

What didn’t work?

percent = “There is a #{rand(101)} chance you’ll like it”
puts percent

works for me. If you mean that it’s always the same percentage, then
make it a method:

def percentage_sentence
“There is a #{rand(101)} chance you’ll like it”
end

puts percent

Jesus.