Idiomatic R for Rosetta Code (2013)
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The document discusses Rosetta Code, an online collection of programming tasks solved in many different languages, and encourages attendees to contribute R solutions to unsolved tasks or improve existing solutions. It also reviews some existing R code on Rosetta Code to discuss idiomatic R style and seeks help with solving the task of finding Pythagorean triples with a given diameter in a functional way.
![<markdown>
=={{header|R}}==
In R most operations work on vectors and matrices:
<lang R># create a 2-times-2 matrix
mat <- matrix(1:4, 2, 2)</lang>
{{out}}
<pre>> mat <- matrix(1:4, 2, 2)
[,1] [,2]
[1,] 1 3
[2,] 2 4</pre>
</markdown>](https://image.slidesharecdn.com/idiomaticrforrosettacode2013-130317151425-phpapp02/85/Idiomatic-R-for-Rosetta-Code-2013-8-320.jpg)
Idiomatic R for Rosetta Code (2013)
- 1. Idiomatic R for Rosetta Code Vienna<-R Meetup II, March 2013 Peter Kofler, ‘Code Cop’ @codecopkofler www.code-cop.org Copyright Peter Kofler, licensed under CC-BY.
- 2. Peter Kofler • Ph.D. (Appl. Math.) • Java et.al. Software Developer for 13 years • „fanatic about code quality“ • R “developer” since 2012
- 3. The opinions expressed here are my own and do not necessarily represent those of current or past employers.
- 4. Rosetta Code
- 5. Rosetta Code ● http://rosettacode.org/ ● programming chrestomathy site ● solutions to same task ● in many different languages ● demonstrate how languages are similar/different
- 6. R „Easy Picks“ ● Some basic samples not set, e.g. ● http://rosettacode.org/wiki/Include_a_file#R ● http://rosettacode.org/wiki/Element-wise_operations#R ● We should search for them and fix ● now you know where to go in your lunch break (instead of Facebook ;-) ● http://rosettacode.org/wiki/Reports:Tasks_not_implemented_in_R
- 7. Solve a Task ● before editing the Rosetta Code page ● read the task ● solve it ● check your solution ● add your code to web ● hit the preview button ● add descriptions to code ● GNU Free Documentation License ● http://rosettacode.org/wiki/Rosetta_Code:Solve_a_Task
- 8. <markdown> =={{header|R}}== In R most operations work on vectors and matrices: <lang R># create a 2-times-2 matrix mat <- matrix(1:4, 2, 2)</lang> {{out}} <pre>> mat <- matrix(1:4, 2, 2) [,1] [,2] [1,] 1 3 [2,] 2 4</pre> </markdown>
- 9. Let's See Some Code
- 10. For Review ● Arithmetic-geometric mean ● http://rosettacode.org/wiki/Arithmetic-geometric_mean ● http://rosettacode.org/wiki/Arithmetic-geometric_mean#R Is it idiomatic? ● ● Fibonacci sequence ● http://rosettacode.org/wiki/Fibonacci_sequence ● http://rosettacode.org/wiki/Fibonacci_sequence#R ● Recursive, iterative or mapping?
- 11. Work in Progress ● Zeckendorf number representation ● http://rosettacode.org/wiki/Zeckendorf_number_representation ● Algorithm: ● get an upper limit on Fibonacci numbers needed to cover number ● return the sequence as digits, sorted descending ● drop leading 0 and convert to String ● Is this nice R?
- 12. PETER KOFLER, CODE-COP.ORG FANATIC ABOUT CODE QUALITY Help Needed ● Pythagorean triples ● http://rosettacode.org/wiki/Pythagorean_triples ● I am stuck! ● How to find all tripples with diameter x in a functional way? ● Is this part of Project Euler problems? Oops!
- 13. Thank You
- 14. Peter Kofler @codecopkofler www.code-cop.org
- 15. CC Images ● Rosetta Stone: http://www.flickr.com/photos/nrbelex/454711486/ ● Judge Dredd: http://www.flickr.com/photos/eldave/6169431454/ ● Matrix: http://www.flickr.com/photos/trinity-of-one/20562069/ ● Questions: http://www.flickr.com/photos/seandreilinger/2326448445/