Extend R with C!!!
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This document discusses extending R with C code. It motivates combining R and C by noting that C code can speed up parts of R programs and allow access to C libraries. It then provides an example of calling a C function from R that returns an integer and examples of passing different R object types to C. It recommends compiling C code into a shared library and loading that into R using dyn.load.
![C R
// integer
int n = INTEGER(exp)[0];
// string
PROTECT(exp = AS_CHARACTER(exp));
char* str = R_alloc(strlen(CHAR(
STRING_ELT(exp, 0))), sizeof(char));
strcpy(str, CHAR(STRING_ELT(exp, 0)));
...
UNPROTECT(1)](https://image.slidesharecdn.com/rdeextention-091122110634-phpapp01/85/Extend-R-with-C-19-320.jpg)
![C R
// integer
SEXP exp_int;
PROTECT(exp_int = NEW_INTEGER(1));
int* pi = INTEGER_POINTER(exp_int);
pi[0] = 24;
...
UNPROTECT(1);
return exp_int;](https://image.slidesharecdn.com/rdeextention-091122110634-phpapp01/85/Extend-R-with-C-20-320.jpg)
Extend R with C!!!
- 1. Extend R with C!!! 2009/11/22 id:mickey24
- 5. ? Tsukuba.R#4 ? R Brainf*ck
- 6. ? Tsukuba.R#4 ? R Brainf*ck ? Tsukuba.R#5 ? Animation with R
- 8. C R
- 9. ? ?
- 10. C R
- 11. C R ?C R
- 12. C R ?C R ?C R C R
- 13. Motivation
- 14. Motivation 1.
- 15. Motivation 1. ?
- 16. Motivation 1. ? ? C R (40 50 ) www - Seeking for my unique color. http://d.hatena.ne.jp/syou6162/20090117/1232120983
- 17. Motivation 1. ? ? C R (40 50 ) www - Seeking for my unique color. http://d.hatena.ne.jp/syou6162/20090117/1232120983 2. R C
- 18. #include <R.h> #include <Rinternals.h> SEXP test(SEXP exp) { ... }
- 19. C R // integer int n = INTEGER(exp)[0]; // string PROTECT(exp = AS_CHARACTER(exp)); char* str = R_alloc(strlen(CHAR( STRING_ELT(exp, 0))), sizeof(char)); strcpy(str, CHAR(STRING_ELT(exp, 0))); ... UNPROTECT(1)
- 20. C R // integer SEXP exp_int; PROTECT(exp_int = NEW_INTEGER(1)); int* pi = INTEGER_POINTER(exp_int); pi[0] = 24; ... UNPROTECT(1); return exp_int;
- 22. $ R CMD SHLIB test.c
- 23. $ R CMD SHLIB test.c ? test.so
- 24. $ R CMD SHLIB test.c ? test.so ? R R
- 25. $ R CMD SHLIB test.c ? test.so ? R R ? Make?le Makevars
- 26. R C dyn.load("test.so") test <- function(n) { .Call("test", integer(n)) } test(24) Writing R Extensions http://cran.r-project.org/doc/contrib/manuals-jp/R-exts.jp.pdf
- 27. ? ?
- 29. ?C R
- 30. ?C R ? C R
- 31. ?C R ? C R ? 6162
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- 34. OpenCV ? ? BSD
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- 36. OpenCV ? ? BSD ? C C++ Python ?
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- 45. ´
- 46. ´ ´
- 49. ?
- 50. ? ?C R
- 51. ? ?C R ?
- 52. ? C R - Seeking for my unique color. http://d.hatena.ne.jp/syou6162/20090117/1232125870 ? Writing R Extensions http://cran.r-project.org/doc/contrib/manuals-jp/R-exts.jp.pdf