Prev: Sinatra without RubyGems
Next: [ANN] Ember 0.1.1
From: Awoke Smith on 22 Apr 2010 18:14
Let's say I have a file named "data1.txt" and "data2.txt" that contain
numbers on seperate lines.

data1.txt contains:
1
3
4
5
6

data2.txt contains:
3
4
6
3
2

How can ruby add the numbers on each line together from the selected
file?

For instance:

Program: "Input a file name: "
User: "data2.txt"
Program: "18"

(because 3+4+6+3+2 = 18)

Program: "Input a file name: "
User: "data1.txt"
Program: "19"

(because 1+3+4+5+6 = 19)

I cannot even get passed opening a file that the user requested:

"print "Type file name: "
file_name = gets

a = []
number_file = open file_name

while x = number_file.gets
a << x
end
puts a
puts"

This would hopefully just repeat the contents of the file_name that the
user inputted (I was going to worry about adding them together later)

This is what happens with the program named "p6.rb" and the data file
containing the numbers named "numbers2.txt" (It contains 2 6 8 9 15 on
seperate lines)

Program: "Type of a file name: "
User: "numbers2.txt"
Program: p6.rb:5:in `initialize': No such file or directory -
numbers2.txt (Errno::ENOENT)
from p6.rb:5:in `open'
from p6.rb:5


Then I change the code to manually input the file name in the code

"a = []
number_file = open "numbers2.txt"

while x = number_file.gets
a << x
end
puts a
puts"

and I get this:

Program:
"2
6
8
9
15"

My biggest question is just how to add the numbers together for any file
that has numbers on different lines like numbers2.txt or data1.txt or
data2.txt

thank you for any reply
--
Posted via http://www.ruby-forum.com/.

From: Robert Dober on 22 Apr 2010 18:21
On Fri, Apr 23, 2010 at 12:14 AM, Awoke Smith <mwksmith(a)gmail.com> wrote:

ARGF.map( &:to_i ).inject( &:+ )

HTH
R.
--
The best way to predict the future is to invent it.
-- Alan Kay

 | 
Pages: 1
Prev: Sinatra without RubyGems
Next: [ANN] Ember 0.1.1