Binary in Elixir
Convert a binary number, represented as a string (e.g. '101010'), to its decimal equivalent using first principles
exercism fetch elixir binary
Convert a binary number, represented as a string (e.g. '101010'), to its decimal equivalent using first principles.
Implement binary to decimal conversion. Given a binary input string, your program should produce a decimal output. The program should handle invalid inputs.
- Implement the conversion yourself. Do not use something else to perform the conversion for you.
About Binary (Base-2)
Decimal is a base-10 system.
A number 23 in base 10 notation can be understood as a linear combination of powers of 10:
- The rightmost digit gets multiplied by 100 = 1
- The next number gets multiplied by 101 = 10
- The n*th number gets multiplied by 10^(n-1)*.
- All these values are summed.
23 => 2*10^1 + 3*10^0 => 2*10 + 3*1 = 23 base 10
Binary is similar, but uses powers of 2 rather than powers of 10.
101 => 1*2^2 + 0*2^1 + 1*2^0 => 1*4 + 0*2 + 1*1 => 4 + 1 => 5 base 10.
Execute the tests with:
$ elixir binary_test.exs
In the test suites, all but the first test have been skipped.
Once you get a test passing, you can unskip the next one by
commenting out the relevant
@tag :pending with a
Or, you can enable all the tests by commenting out the
ExUnit.configure line in the test suite.
# ExUnit.configure exclude: :pending, trace: true
For more detailed information about the Elixir track, please see the help page.
All of Computer Science http://www.wolframalpha.com/input/?i=binary&a=*C.binary-_*MathWorld-
Submitting Incomplete Solutions
It's possible to submit an incomplete solution so you can see how others have completed the exercise.