rails convert string to number

Question

I am wondering what is a convenient function in Rails to convert a string with a negative sign into a number. e.g. -1005.32

When I use the .to_f

Answer 1

You should be using Kernel::Float to convert the number; on invalid input, this will raise an error instead of just "trying" to convert it.

>> "10.5".to_f
=> 10.5
>> "asdf".to_f # do you *really* want a zero for this?
=> 0.0
>> Float("asdf")
ArgumentError: invalid value for Float(): "asdf"
    from (irb):11:in `Float'
    from (irb):11
>> Float("10.5")
=> 10.5