如何从ruby中的字符串中提取浮点数？

Question

我有一些不同货币的字符串，例如

"454,54$", "Rs566.33", "discount 88,0$" etc.

模式不一致，我想从字符串和货币中仅提取浮点数。

我如何在Ruby中实现这一目标？

Answer 1

您可以使用此正则表达式匹配您发布的两种格式的浮点数： -

(\d+[,.]\d+)

请参阅Demo on Rubular

Answer 2

你可以试试这个：

["454,54$", "Rs566.33", "discount 88,0$", "some string"].each do |str|
  # making sure the string actually contains some float
  next unless float_match = str.scan(/(\d+[.,]\d+)/).flatten.first
  # converting matched string to float
  float = float_match.tr(',', '.').to_f
  puts "#{str} => %.2f" % float
end

# => 454,54$ => 454.54
# => Rs566.33 => 566.33
# => discount 88,0$ => 88.00

Demo on CIBox