Ruby program for searching words in a file - ruby

Question

I started with Ruby yesterday, I only have some experience with C.
Now I'm trying to write a program that gets a file and a word to search in that file from ARGV, and prints how many times the word appeared. Got rid of any error, but it prints 0 anyway when I test it.
if ARGV.size !=2
puts "INSERT A FILE AND A WORD OR A CHAR TO SEARCH FOR"
exit 1
else
file = File.open(ARGV[0], mode = "r")
word = ARGV[1]
if !file
puts "ERROR: INVALID INPUT FILE"
exit 1
end
while true
begin
i = 0
count_word = 0
string = []
string[i] = file.readline
if string[i].upcase.include? word.upcase
count_word += 1
end
i += 1
rescue EOFError
break
end
end
print "The word searched is ", word, " Frequency: ", count_word, "\n"
end
I hope you could tell me what's wrong (I believe I do something wrong when counting), thanks in advance.

Answer 1

A great thing about Ruby it that it operates on a way higher level of abstraction. Here is a snippet that does what you want:
if ARGV.size != 2
puts "Provide file to be searched in and word to be found"
exit 1
end
file = ARGV[0]
word = ARGV[1]
count = 0
File.open(file, 'r').each { |line| count += 1 if line.downcase.include? word.downcase }
puts "The word searched is #{word} Frequency: #{count}"
As you can see, the language provides a lot of features like string interpolation, enumeration of the file contents, etc.
There is a handful of problems with the code you provided. From styling issues like indentation, to incorrect assumptions about the language like the if !file check and strange decisions overall - like why do you use a list if you want only the current line.
I suggest you to look at http://tryruby.org/ . It is very short and will get you a feel of the Ruby way to do things. Also it covers your question (processing files).
As a general note when you post a question on stackoverflow, please include the code in the question, rather than link to an external page. This way people can read through it faster, edit it and the code wont be lost if the other site goes down. You can still link to external pages if you want to show the snippet in action.

Answer 2

Hope this will help you, the error that you did is that you included this part:
i = 0
count_word = 0
string = []
into the while loop, which every time resets your counter to zero even if it found the word, so to correct this error here what you should do:
if ARGV.size !=2
puts "INSERT A FILE AND A WORD OR A CHAR TO SEARCH FOR"
exit 1
else
file = File.open(ARGV[0], mode = "r")
word = ARGV[1]
if !file
puts "ERROR: INVALID INPUT FILE"
exit 1
end
i = 0
count_word = 0
string = []
while true
begin
string[i] = file.readline
if string[i].upcase.include? word.upcase
count_word += 1
end
i += 1
rescue EOFError
break
end
end
print "The word searched is ", word, " Frequency: ", count_word, "\n"
end