completed assignment

Gemfile

@@ -1,6 +1,6 @@
 source 'http://rubygems.org'
 
-ruby '2.6.6'
+ruby '2.6.5'
 
 gem 'rake'
 

lib/binary_to_decimal.rb

@@ -5,5 +5,12 @@
 # Calculate  and return the decimal value for this binary number using
 # the algorithm you devised in class.
 def binary_to_decimal(binary_array)
-  raise NotImplementedError
+  dec = 0
+  i = 0
+  while i < binary_array.length
+    dec += binary_array[i] * 2 ** (binary_array.length - 1 - i)
+    i += 1
+  end
+  return dec
 end
+

lib/decimal_to_binary.rb

@@ -0,0 +1,20 @@
+
+def decimal_to_binary(decimal)
+  bin = Array.new(8)
+  i = 0
+
+  while i < bin.length
+
+    if(decimal - 2 ** (bin.length - 1 - i) < 0)
+      bin[i] = 0
+    else
+      bin[i] = 1
+      decimal -= 2 ** (bin.length - 1 - i)
+    end
+    i += 1
+  end
+
+
+  return bin
+end
+

test/decimal_to_binary_test.rb

@@ -0,0 +1,33 @@
+require 'minitest/autorun'
+require 'minitest/reporters'
+require_relative '../lib/decimal_to_binary'
+
+Minitest::Reporters.use! Minitest::Reporters::SpecReporter.new
+
+describe "decimal to binary" do
+  it "From 153 to 10011001" do
+
+    decimal = 153
+    expected_binary_array = [1, 0, 0, 1, 1, 0, 0, 1]
+
+    expect(decimal_to_binary(decimal)).must_equal expected_binary_array
+  end
+
+  it "From 13 to 00001101" do
+
+    decimal = 13
+    expected_binary_array = [0, 0, 0, 0, 1, 1, 0, 1]
+
+    expect(decimal_to_binary(decimal)).must_equal expected_binary_array
+  end
+
+  it "From 128 to 10000000" do
+
+    expected_binary_array = [1, 0, 0, 0, 0, 0, 0, 0]
+    decimal = 128
+
+    expect(decimal_to_binary(decimal)).must_equal expected_binary_array
+  end
+
+
+end