Space Age in Common Lisp
Given an age in seconds, calculate how old someone is in terms of a given planet's solar years.
exercism fetch common-lisp space-age
Given an age in seconds, calculate how old someone would be on:
- Earth: orbital period 365.25 Earth days, or 31557600 seconds
- Mercury: orbital period 0.2408467 Earth years
- Venus: orbital period 0.61519726 Earth years
- Mars: orbital period 1.8808158 Earth years
- Jupiter: orbital period 11.862615 Earth years
- Saturn: orbital period 29.447498 Earth years
- Uranus: orbital period 84.016846 Earth years
- Neptune: orbital period 164.79132 Earth years
So if you were told someone were 1,000,000,000 seconds old, you should be able to say that they're 31.69 Earth-years old. Round all ages to the nearest hundredth of a year.
If you're wondering why Pluto didn't make the cut, go watch this youtube video.
Check out Exercism Help for instructions to get started writing Common Lisp. That page will explain how to install and setup a Lisp implementation and how to run the tests.
While Common Lisp doesn't care about indentation and layout of code, nor whether you use spaces or tabs, this is an important consideration for submissions to exercism.io. Excercism.io's code widget cannot handle mixing of tab and space characters well so using only spaces is recommended to make the code more readable to the human reviewers. Please review your editors settings on how to accomplish this. Below are instructions for popular editors for Common Lisp.
Use the following commands to ensure VIM uses only spaces for indentation:
(or as a oneliner
:set tabstop=2 shiftwidth=2 expandtab). This can
be added to your
~/.vimrc file to use it all the time.
Emacs is very well suited for editing Common Lisp and has many powerful add-on packages available. The only thing that one needs to do with a stock emacs to make it work well with exercism.io is to evaluate the following code:
(setq indent-tab-mode nil)
This can be placed in your
order to have it set whenever Emacs is launched.
One suggested add-on for Emacs and Common Lisp is SLIME which offers tight integration with the REPL; making iterative coding and testing very easy.
Partially inspired by Chapter 1 in Chris Pine's online Learn to Program tutorial. http://pine.fm/LearnToProgram/?Chapter=01
Submitting Incomplete Solutions
It's possible to submit an incomplete solution so you can see how others have completed the exercise.