ruby converting a string into float destroys the digit

Question

I have the following code:

input=File.open("lala.txt","r")
genes=[]

input.each_line{|li|

    keys=li.split("\t")
    length=keys.length
    puts(keys[length-2])
    puts(keys[length-2].to_f)

    if (keys[0]["-"].class==NilClass && keys[1]["-"].class==NilClass && (keys[length-2]).to_f>0.98)
    genes.push(keys[0])
    genes.push(keys[1])
    end

}

inputfile:

1053_at/RFC2    203696_s_at/RFC2    0.9031699692435061  
117_at/HSPA6    1553158_at/C3orf34  0.9079515773059148  
117_at/HSPA6    1553513_at/VNN3 0.9237382047518812  
117_at/HSPA6    1553723_at/GPR97    0.9367168572635286  
117_at/HSPA6    1557852_at/---  0.9177916032275163  
117_at/HSPA6    1558525_at/---  0.9229865774037962  
117_at/HSPA6    1562481_at/---  0.9109034368848434  
117_at/HSPA6    1569385_s_at/TET2   0.9187904542249753  
117_at/HSPA6    1569830_at/PTPRC    0.900051189462974   
117_at/HSPA6    1569955_at/---  0.9028606652628463  
117_at/HSPA6    201393_s_at/IGF2R   0.9090699277161238

My problem is following: I want to compare the number in each row with >0.98.
If I write it just keys[length-2]>0.98it shows me an error that I want to compare a String with a float. OK. Lets convert a String to Float then by doing this: (keys[length-2]).to_f . In converted it BUT it destroys the number: I get 0.0

output:

0.9031699692435061
0.0
0.9079515773059148
0.0
0.9237382047518812
0.0
0.9367168572635286
0.0
0.9177916032275163
0.0
0.9229865774037962
0.0
0.9109034368848434
0.0
0.9187904542249753
0.0
0.900051189462974
0.0
0.9028606652628463
0.0
0.9090699277161238
0.0
0.9002336615360215
0.0

What is wrong then?(Ruby: linux 1.9.3) Thanks in advance

Answer 1

judging by all the null bytes in there, what you've got is utf16 text that you are interpreting as utf8 or ascii. Assuming you are on ruby 1.9, you can get ruby to do the encoding by doing

File.open("lala.txt","rb:UTF-16:US-ASCII")

which will convert the text into the default internal encoding.

Answer 2

Your code could be written more Ruby-like, and take advantage of a well-tested wheel:

require 'csv'

genes = []
CSV.foreach("lala.txt", :col_sep => "\t") do |row|

  puts row[-1]
  puts row[-1].to_f

  if (!row[0]["-"] && !row[1]["-"] && (row[-1].to_f > 0.98))
    genes << row[0]
    genes << row[1]
  end

end

puts genes

This is the output:

0.9031699692435061
0.9031699692435061
0.9079515773059148
0.9079515773059148
0.9237382047518812
0.9237382047518812
0.9367168572635286
0.9367168572635286
0.9177916032275163
0.9177916032275163
0.9229865774037962
0.9229865774037962
0.9109034368848434
0.9109034368848434
0.9187904542249753
0.9187904542249753
0.900051189462974
0.900051189462974
0.9028606652628463
0.9028606652628463
0.9090699277161238
0.9090699277161238

And genes is empty because no values in the last column are > 0.98.

Answer 3

I think you've got some weird whitespace issues. I think if you split on /\s+/ and just use keys.last you should be good:

input=File.open("lala.txt","r")
genes=[]

input.each_line{|li|
  keys=li.split(/\s+/)
  puts(keys.last)
  puts(keys.last.to_f)

  if (keys[0]["-"].class==NilClass && keys[1]["-"].class==NilClass && (keys.last).to_f>0.98)
    genes.push(keys[0])
    genes.push(keys[1])
  end
}