Formatting values in Ruby

Strings and Regular Expressions example from a Well House Consultants training course
More on Strings and Regular Expressions [link]

This example is described in the following article(s):
• Divide 10000 by 17. Do you get 588.235294117647, 588.24 or 588? - Ruby and PHP - [link]

Source code: kids Module: R109

# Formatting values in Ruby

# Ruby has a sprintf function and also a % operator
# Python just has the % operator
# C and Perl have printf and sprintf

maxfavoured = 17

winnings = 10000.00

for infavour in 1..maxfavoured
        amount = winnings / infavour
        puts "With #{'%-2d' % infavour} kids, each gets #{'%8.2f' % amount}"
        puts "With #{sprintf '%-2d',infavour} kids, each gets #{sprintf '%8.2f',amount}"
end

__END__

Format strings ...

        %....d Integer - base 10 (decimal)
        %....x Integer - base 16 (hexadecimal)
        %....o Integer - base 8 (octal)
        %....b Integer - base 2 (binary)

        %....f Float
        %....e Exponential
        %....g General format (f or e - chosen by Ruby)

        %....s String

        %% I REALLY want a % character!

Examples:

        %8.2f Float, 2 figs after decimal point
                total width of at least 8 characters
        %2d Integer, base 10, 2 character positions
        %02d ditto, leading zero filled
        %-2d ditto, left justified not right

munchkin:rs grahamellis$ ruby kids
With 1 kids, each gets 10000.00
With 1 kids, each gets 10000.00
With 2 kids, each gets 5000.00
With 2 kids, each gets 5000.00
With 3 kids, each gets 3333.33
With 3 kids, each gets 3333.33
With 4 kids, each gets 2500.00
With 4 kids, each gets 2500.00
With 5 kids, each gets 2000.00
With 5 kids, each gets 2000.00
With 6 kids, each gets 1666.67
With 6 kids, each gets 1666.67
With 7 kids, each gets 1428.57
With 7 kids, each gets 1428.57
With 8 kids, each gets 1250.00
With 8 kids, each gets 1250.00
With 9 kids, each gets 1111.11
With 9 kids, each gets 1111.11
With 10 kids, each gets 1000.00
With 10 kids, each gets 1000.00
With 11 kids, each gets 909.09
With 11 kids, each gets 909.09
With 12 kids, each gets 833.33
With 12 kids, each gets 833.33
With 13 kids, each gets 769.23
With 13 kids, each gets 769.23
With 14 kids, each gets 714.29
With 14 kids, each gets 714.29
With 15 kids, each gets 666.67
With 15 kids, each gets 666.67
With 16 kids, each gets 625.00
With 16 kids, each gets 625.00
With 17 kids, each gets 588.24
With 17 kids, each gets 588.24
munchkin:rs grahamellis$

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This module and example are covered on the following public courses:
* Learning to program in Ruby
* Ruby Programming
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