Ruby one liner killed my script

Talk about redundancy!

I spent some time with irb with the aim of getting an understanding of
methods and class building. I originally wanted to convert a binary
number to denary, with input from the user.

strike one!

ruby -e ‘p 0b10010101111’
does it on one line.

Anyway, I still looked at the few lines that I had and I’m wondering
how I can convert a user’s input into a fixnum?

class B2d
def initialize
@ustring = " "
end

def get_bin_string
p 'binary numbers : ’
@ustring = gets.chomp
end

def test_bin_string
if @ustring =~ /[a-z]|[2-9]|[A-Z]| /
p “binary digits only and no spaces, please!”
exit 1
end
end

def put_bin_string

this is the line in which I originally tried to convert the user’s

binary digit to denary puts “your bin #{@ustring.to_i} =
0b#{@ustring.to_i}” end
end

t = B2d.new
t.get_bin_string
t.test_bin_string
t.put_bin_string

Regards,

John M.

Regards,

John M.
MSc (DIC)
+44 7739 171 531

John M. wrote:

I’m wondering
how I can convert a user’s input into a fixnum?

def put_bin_string

this is the line in which I originally tried to convert

the user’s binary digit to denary:

puts “your bin #{@ustring.to_i} =
0b#{@ustring.to_i}” end
end

Does this help:

input = “10000001”
puts input.to_i(base=2)

–output:–
129

Where can I find out more about that method within ri?
ri Object?

On Tue, 12 Feb 2008 09:50:25 +0900
7stud – [email protected] wrote:

end

Does this help:

input = “10000001”
puts input.to_i(base=2)

–output:–
129

Regards,

John M.
MSc (DIC)
+44 7739 171 531

From: John M. [mailto:[email protected]]

Where can I find out more about that method within ri?

ri Object?

judging fr stud’s reply, maybe you can try the string object first, eg,

botp@pc4all:~$ qri to_i
------------------------------------------------------ Multiple choices:

 Class#to_i, Float#to_i, IO#to_i, IPAddr#to_i, Integer#to_i,
 NilClass#to_i, Process::Status#to_i, Rational#to_i, String#to_i,
 Symbol#to_i, Time#to_i

botp@pc4all:~$ qri string.to_i
------------------------------------------------------------ String#to_i
str.to_i(base=10) => integer

 Returns the result of interpreting leading characters in str as an
 integer base base (2, 8, 10, or 16). Extraneous characters past
 the end of a valid number are ignored. If there is not a valid
 number at the start of str, 0 is returned. This method never
 raises an exception.

    "12345".to_i             #=> 12345
    "99 red balloons".to_i   #=> 99
    "0a".to_i                #=> 0
    "0a".to_i(16)            #=> 10
    "hello".to_i             #=> 0
    "1100101".to_i(2)        #=> 101
    "1100101".to_i(8)        #=> 294977
    "1100101".to_i(10)       #=> 1100101
    "1100101".to_i(16)       #=> 17826049

botp@pc4all:~$

kind regards -botp