Re: storing and manipulating columns of data

baptiste Auguié wrote:
Hi,

Being used to deal with Octave / Matlab, I'm a bit confused by Ruby structures (arrays, hashes, etc). I have this data file "data.dat" with 3 columns:

I would like to think of the columns as arrays "a", "b", "c", execute a loop along their indices, pick the values i want, and do something with them. What would be a sensible data structure for this?
I can read this datafile line by line using IO:readlines("data.dat"), but I cannot find a way to refer to one column in the array of strings generated.

You can use String#split to split each line into an array of 3 numbers. If you want to use the array values as numbers, you'll need to use String#to_f as well to convert the strings to numeric values.

ri String#split
ri String#to_f

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