From 3996a06369559416ca764af474f7b33a9d49d978 Mon Sep 17 00:00:00 2001
From: Gaurav Agarwal <algogrit@gmail.com>
Date: Sat, 12 Oct 2019 13:52:48 +0530
Subject: [PATCH] Explaining compounding with a ruby script.

---
 .ruby-version          |  1 +
 Gemfile                |  7 +++++++
 Gemfile.lock           | 13 +++++++++++++
 explain-compounding.rb | 15 +++++++++------
 4 files changed, 30 insertions(+), 6 deletions(-)
 create mode 100644 .ruby-version
 create mode 100755 Gemfile
 create mode 100644 Gemfile.lock

diff --git a/.ruby-version b/.ruby-version
new file mode 100644
index 0000000..ec1cf33
--- /dev/null
+++ b/.ruby-version
@@ -0,0 +1 @@
+2.6.3
diff --git a/Gemfile b/Gemfile
new file mode 100755
index 0000000..53c9a95
--- /dev/null
+++ b/Gemfile
@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+source "https://rubygems.org"
+
+git_source(:github) {|repo_name| "https://github.com/#{repo_name}" }
+
+gem "humanize"
diff --git a/Gemfile.lock b/Gemfile.lock
new file mode 100644
index 0000000..72b0d3b
--- /dev/null
+++ b/Gemfile.lock
@@ -0,0 +1,13 @@
+GEM
+  remote: https://rubygems.org/
+  specs:
+    humanize (2.2.1)
+
+PLATFORMS
+  ruby
+
+DEPENDENCIES
+  humanize
+
+BUNDLED WITH
+   2.0.2
diff --git a/explain-compounding.rb b/explain-compounding.rb
index 6e809a3..4569563 100755
--- a/explain-compounding.rb
+++ b/explain-compounding.rb
@@ -1,7 +1,9 @@
 #!/usr/bin/env ruby
 
-initial_amount = 100000
-rate = 7
+require 'humanize'
+
+initial_amount = 1_26_000
+rate = 9.0
 years = 10
 
 puts "Use defaults - Amount: #{initial_amount}, Rate: #{rate}, Years: #{years}?"
@@ -12,7 +14,7 @@
   initial_amount = gets.to_i
 
   puts "Enter rate of interest: "
-  rate = gets.to_i
+  rate = gets.to_f
 
   puts "Enter total years: "
   years = gets.to_i
@@ -20,10 +22,11 @@
 
 amount = initial_amount
 
-puts "You invested #{amount}"
+puts "You invested \"#{amount.humanize}\" for #{years} years at #{rate}% compounded"
+
 years.times do |i|
-  amount = amount * ( 1 + (rate / 100.0) )
-  puts "At end of #{i+1} year: #{amount}"
+  amount = (amount * ( 1 + (rate / 100.0) )).round(2)
+  puts "At end of #{i+1} year: #{amount} or \"#{amount.humanize}\""
 end
 
 puts "If you invest it for another #{years} years: #{amount * (( 1 + (rate / 100.0) ) ** years)}"