Ruby one liner killed my script

[John Maclean]

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 Maclean


--

Regards,

John Maclean
MSc (DIC)
+44 7739 171 531

 

[7stud --]

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

 

[John Maclean]

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

Does this help:

input = "10000001"
puts input.to_i(base=2)

--output:--
129

--

Regards,

John Maclean
MSc (DIC)
+44 7739 171 531

 

[Peña, Botp]

From: John Maclean [mailto:[email protected]]=20
# 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=3D10) =3D> 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 #=3D> 12345
"99 red balloons".to_i #=3D> 99
"0a".to_i #=3D> 0
"0a".to_i(16) #=3D> 10
"hello".to_i #=3D> 0
"1100101".to_i(2) #=3D> 101
"1100101".to_i(8) #=3D> 294977
"1100101".to_i(10) #=3D> 1100101
"1100101".to_i(16) #=3D> 17826049

botp@pc4all:~$

kind regards -botp