Specifying how many numbers after a decimal point

Question

 a = '60.950'
 b = a.to_f

 puts a # => 60.950
 puts b # => 60.95

I want to display three digits after the decimal point everytime. How can I force 0 at the end of b?

Answer 1

Use sprintf.

sprintf('%.3f', 60.95)
# => "60.950"

Answer 2

Use the mother of the formatting methods, such as String#% or printf or sprintf, which is Kernel#format

puts format('%.3f', 0)

The others refer to this, and the Kernel#format documentation has the full documentation tables.