From: Josh Cheek <josh.cheek@...>
Date: 2010-04-14T11:36:34+09:00
Subject: Re: Method to groom a string to floating point representation

--000e0cd13a0208fd8b0484293fe3
Content-Type: text/plain; charset=windows-1252
Content-Transfer-Encoding: quoted-printable

On Tue, Apr 13, 2010 at 6:20 AM, Alex DeCaria <alex.decaria@millersville.ed=
u
> wrote:

> Delete any decimals in an exponent:
> '245e7.6' =3D> '2.45e76'
>

Where did the dot in between 2 and 4 come from? Am I interpreting the Strin=
g
or just cleaning it?


> Delete any extra or misplaced + or =96 signs:
> '+45-68+e+45-' =3D> '4568e+45'
>
> Delete any extra or misplaced =91e=92 or =91E=92 characters (first occura=
nce of
> '+e4.67e-7' =3D> '+4.67e-7'
>
>
Why does the plus in front of 45 in the first one go away, but the plus in
front of the e in the second one stays?

-----

This is what I have so far, please check and correct any tests that should
be different

def clean_string( str , options =3D Hash.new )
  str =3D~ /\A([-+]?)([^eE.]*\.?)([^eE]*)((?:[eE][+-]?)?)([^Z]*)\Z/
  posneg , prepre , postpre , e , post =3D $1 , $2 , $3 , $4 , $5
  posneg + prepre + postpre.gsub(/[^0-9]/,'') + e + post.gsub(/[^0-9]/,'')
end

require 'test/unit'
class TestCleanString < Test::Unit::TestCase
  def test_delete_chars
    assert_equal '-24.5e45' , clean_string('-24.5fge4x5')
  end
  def test_delete_extra_decimal
    assert_equal '2.45' , clean_string('2.4.5')
    assert_equal '2.45' , clean_string('2..45')
    assert_equal '2.45' , clean_string('2...45')
  end
  def test_delete_extra_decimal_in_exponent
    assert_equal '245e76' , clean_string('245e7.6') # you said this should
be '2.45e76' , but where did first dot come from?
  end
  def test_delete_extra_or_misplaced_pos_and_neg_signs
    assert_equal '4568e+45' , clean_string('+45-68+e+45-')
  end
  def test_delete_extra_or_misplaced_e_or_E
    assert_equal '4.67e67'  , clean_string('4.67e6e-7')
    assert_equal '+4.67e-7' , clean_string('+e4.67e-7')
  end
end

--000e0cd13a0208fd8b0484293fe3--