Re: reading data files with headers and columns

Thanks very much Luc, here are a few follow up questions (complete
noob)

# here's the columns as arrays
  @column1 =3D []  # should this be @column1=3D[variable1] or just the
empty square brackets?
  <rest_of_columns>
  # open file in read mode (r)
  file =3D File.new("<your_filename", "r")
  # read each line one after another and process it
  file.each_line do |line|   # where do I specify how the header is to
be skipped, how many lines to
#be skipped or otherwise processed?
    # process as header if necessary
    # or
    # extract your variables in the line into an array
    array =3D line.split("<your_column_separator>") # I am guessing that
a space column separator
#would be " ", does it work with arbit number of multiple spaces
between the columns i.e. if the
#column width is variable but between two
# columns there are one or several spaces?
    # assign variable to column
    @column1 << array[0]
# if @column1=3D[variable1] comment in the second line of the above code
was not correct, then
#where do the variables get their names?
    # ... process other columns
  end


On Mar 13, 1:23=A0pm, Luc Traonmilin <[e-mail]> wrote:
> Yaj Bhattacharya a =E9crit :
>
>
>
> > Hello,
>
> > As a noob to Ruby, I need to read a data file with the first few lines
> > as header, then the rest of the file as columns of different variables
> > as arrays (in this case, 5 columns).
> > After reading in the variables, I want to calculate some operations
> > with each unique data field address (e.g. column3, row4), then write
> > out the file with headers and data in columns.
>
> > Could someone help with a few lines of basic code?
>
> > Thanks in advance
> > Yaj
>
> You could start with this basic piece of code (replace <tags> with your
> code):
> =A0 # here's the columns as arrays
> =A0 @column1 =3D []
> =A0 <rest_of_columns>
> =A0 # open file in read mode (r)
> =A0 file =3D File.new("<your_filename", "r")
> =A0 # read each line one after another and process it
> =A0 file.each_line do |line|
> =A0 =A0 # process as header if necessary
> =A0 =A0 # or
> =A0 =A0 # extract your variables in the line into an array
> =A0 =A0 array =3D line.split("<your_column_separator>")
> =A0 =A0 # assign variable to column
> =A0 =A0 @column1 << array[0]
> =A0 =A0 # ... process other columns
> =A0 end
>
> Additionnally you can google "ruby array" and "ruby file", the API docs
> are well documented.
>
> Luc- Hide quoted text -
>
> - Show quoted text -