Formatted printing - Ruby example

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):
• Regular Expressions in Ruby - [link]

Source code: d4_6 Module: R109

# Formatted printing in Ruby - printf sprintf and %

gift = 1000.0

# --------- plain print - just output the data

for kids in 1..15
        egets = gift / kids
        print "With #{kids} children, each would get #{egets} pounds\n";
        end

# ---------- printf - formatted print; more flexible

# with %....letter we're telling printf that we want to fill something in.
# %8.2f - a float, 8 characters wide, of which 2 are after the decimal place

for kids in 1..15
        egets = gift / kids
        printf("With %2d children, each would get %8.2f pounds\n",kids,egets)
        end

# ----------- sprintf - more flexible and we can do other things after formatting

flout = File.new "gerald.txt","w"
for kids in 1..15
        egets = gift / kids
        stuff = sprintf("With %2d kiddos, each would get %8.2f pounds\n",kids,egets)
        stuff = ">> " + stuff
        flout.write stuff
        end
flout.close

__END__

Sample Output

-bash-3.2$ ruby d4_6
With 1 children, each would get 1000.0 pounds
With 2 children, each would get 500.0 pounds
With 3 children, each would get 333.3333333333333 pounds
With 4 children, each would get 250.0 pounds
With 5 children, each would get 200.0 pounds
With 6 children, each would get 166.66666666666666 pounds
With 7 children, each would get 142.85714285714286 pounds
With 8 children, each would get 125.0 pounds
With 9 children, each would get 111.11111111111111 pounds
With 10 children, each would get 100.0 pounds
With 11 children, each would get 90.9090909090909 pounds
With 12 children, each would get 83.33333333333333 pounds
With 13 children, each would get 76.92307692307692 pounds
With 14 children, each would get 71.42857142857143 pounds
With 15 children, each would get 66.66666666666667 pounds
With 1 children, each would get 1000.00 pounds
With 2 children, each would get 500.00 pounds
With 3 children, each would get 333.33 pounds
With 4 children, each would get 250.00 pounds
With 5 children, each would get 200.00 pounds
With 6 children, each would get 166.67 pounds
With 7 children, each would get 142.86 pounds
With 8 children, each would get 125.00 pounds
With 9 children, each would get 111.11 pounds
With 10 children, each would get 100.00 pounds
With 11 children, each would get 90.91 pounds
With 12 children, each would get 83.33 pounds
With 13 children, each would get 76.92 pounds
With 14 children, each would get 71.43 pounds
With 15 children, each would get 66.67 pounds
-bash-3.2$

Learn about this subject

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