How to allow comma when inputting numeric value

Question

I tried to sum two floating point numbers. When I use "." as the delimiter between decimals, it works correctly. But, when I use a comma, the last two numbers return zero. Example:

puts "Type the first number:"
firstNum = gets.to_f # I typed 55,11

puts "Type the second number:"
secondNum = gets.to_f # I typed 45,44

result = firstNum +  secondNum

puts sprintf('%.2f', result)  # Return 100.00

If I use "." to separate the numbers, the return is 100.55.

In ruby decimal deparator is a dot, regardless of what it is for your current computer locale. — Sergio Tulentsev, Mar 12 '17 at 15:01

score 2 · Answer 1 · answered Mar 12 '17 at 14:59

2

Fixnum#to_f expects dots. To allow commas you should do convert them to commas explicitly:

puts "Type the first number:"
#               ⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓
firstNum = gets.tr(',', '.').to_f # I typed 55,11

puts "Type the second number:"
#                ⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓⇓
secondNum = gets.tr(',', '.').to_f # I typed 45,44

result = firstNum +  secondNum

puts sprintf('%.2f', result)  # Return 100.55

answered Mar 12 '17 at 14:59

Aleksei Matiushkin

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Let's hope we don't have a user who enters `1,234.56`. – Cary Swoveland Mar 12 '17 at 20:43

How to allow comma when inputting numeric value

1 Answers1