Skip to content
Open
Show file tree
Hide file tree
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
14 changes: 12 additions & 2 deletions lib/binary_to_decimal.rb
Original file line number Diff line number Diff line change
Expand Up @@ -4,6 +4,16 @@
# The least significant bit is at index 7.
# 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
end
decimal = 0
i = 1
binary_array.each do |value|
power = binary_array.length - i
number = value * (2 ** power)
decimal += number
i += 1
end
return decimal
end
14 changes: 7 additions & 7 deletions test/binary_to_decimal_test.rb
Original file line number Diff line number Diff line change
Expand Up @@ -6,28 +6,28 @@
it "From 10011001 to 153" do
binary_array = [1, 0, 0, 1, 1, 0, 0, 1]
expected_decimal = 153

binary_to_decimal(binary_array).must_equal expected_decimal
end

it "From 00001101 to 13" do
binary_array = [0, 0, 0, 0, 1, 1, 0, 1]
expected_decimal = 13

binary_to_decimal(binary_array).must_equal expected_decimal
end

it "From 10000000 to 128" do
binary_array = [1, 0, 0, 0, 0, 0, 0, 0]
expected_decimal = 128

binary_to_decimal(binary_array).must_equal expected_decimal
end

it "From random binary to decimal" do
binary_array = Array.new(8) { rand(0..1) }
expected_decimal = binary_array.join.to_s.to_i(2)

binary_to_decimal(binary_array).must_equal expected_decimal
end
end