how to parse a float from an string pattern

Question

I am having a string with the following patter

"00:00:30.04,"

Which would be the smartest way to parse this string into a float?

best, phil

maerics · Accepted Answer · 2013-02-04 21:23:24Z

2

s = "00:00:30.04,"
s.split(/[^\deE\.+-]/).map(&:to_f) # => [0.0, 0.0, 30.04]

answered Feb 4, 2013 at 21:23

maerics

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Comments

steenslag · Accepted Answer · 2013-02-04 21:30:19Z

2

p "00:00:30.04,"[6,5].to_f # 30.04
p Float("00:00:30.04,"[6,5]) # 30.04

p "abcdefg"[6,5].to_f # 0.0
p Float("abcdefg"[6,5]) #ArgumentError

Essentially: take a substring starting at position 6 with a length of 5 and return a float based on that. Float is stricter then String.to_f.

answered Feb 4, 2013 at 21:30

steenslag

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Alex Wayne · Accepted Answer · 2013-02-04 21:23:06Z

1

You have 3 numbers there. Split them up, and simply call #to_f (meaning "to float") on each string.

string = "00:00:30.04,"
strings = string.split ":"
numbers = strings.map { |s| s.to_f }
numbers # => [0.0, 0.0, 30.04]

answered Feb 4, 2013 at 21:23

Alex Wayne

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sbagdat · Accepted Answer · 2013-02-04 21:53:32Z

1

if seperator is always colon or coma, you can use following:

"00:00:30.04,".split(/:|,/).map(&:to_f) #=> [0.0, 0.0, 30.04]

answered Feb 4, 2013 at 21:53

sbagdat

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