Look up the Stan function that corresponds to a R function or name.

This function helps to map between R functions and Stan functions.

Usage

lookup(FUN, ReturnType = character())

Arguments

FUN: A character string naming a R function or a R function for which the (near) equivalent Stan function is sought. If no matching R function is found, FUN is reinterpreted as a regexp and matches are sought.
ReturnType: A character string of positive length naming a valid return type for a Stan function: int, int[], matrix, real, real[,], real[], row_vector, T[], vector, or void. If "ANY" is passed, then the entire data.frame is returned and can be inspected with the View function, for example.

Value

Ordinarily, a data.frame with rows equal to the number of partial matches and four columns:

StanFunction Character string for the Stan function's name.
Arguments Character string indicating the arguments to that Stan function.
ReturnType Character string indicating the return type of that Stan function.
Page Integer indicating the page of the Stan reference manual where that Stan function is defined.

If there are no matching Stan functions, a character string indicating so is returned.

References

The Stan Development Team Stan Modeling Language User's Guide and Reference Manual. https://mc-stan.org/.

The Stan Development Team CmdStan Interface User's Guide. https://mc-stan.org.

Examples

lookup(dnorm)      # Stan equivalents for the normal PDF (in log form)
#>           StanFunction
#> 415 normal_id_glm_lpdf
#> 418         normal_log
#> 419        normal_lpdf
#> 553    std_normal_lpdf
#>                                                                        Arguments
#> 415 (real, matrix, real, vector, T);(vector, row_vector, vector, vector, vector)
#> 418                                     (real, real, T);(vector, vector, vector)
#> 419                                     (real, real, T);(vector, vector, vector)
#> 553                                                                 (T);(vector)
#>     ReturnType
#> 415     T;real
#> 418     T;real
#> 419     T;real
#> 553     T;real
lookup("foo")      # fails
#> [1] "no matching Stan functions"
lookup("Student")  # succeeds even though there is no such R function
#>                      StanFunction
#> 374 multi_student_t_cholesky_lpdf
#> 375  multi_student_t_cholesky_rng
#> 376           multi_student_t_log
#> 377          multi_student_t_lpdf
#> 378           multi_student_t_rng
#> 557            student_t_ccdf_log
#> 558                 student_t_cdf
#> 559             student_t_cdf_log
#> 560               student_t_lccdf
#> 561                student_t_lcdf
#> 562                 student_t_log
#> 563                student_t_lpdf
#> 564                 student_t_rng
#>                                                     Arguments
#> 374                            (vector, real, vector, matrix)
#> 375 (real, vector, matrix);(real, array[] row_vector, matrix)
#> 376                            (vector, real, vector, matrix)
#> 377                            (vector, real, vector, matrix)
#> 378 (real, vector, matrix);(real, array[] row_vector, matrix)
#> 557    (real, real, real, T);(vector, vector, vector, vector)
#> 558    (real, real, real, T);(vector, vector, vector, vector)
#> 559    (real, real, real, T);(vector, vector, vector, vector)
#> 560    (real, real, real, T);(vector, vector, vector, vector)
#> 561    (real, real, real, T);(vector, vector, vector, vector)
#> 562    (real, real, real, T);(vector, vector, vector, vector)
#> 563    (real, real, real, T);(vector, vector, vector, vector)
#> 564                             (int, int, T);(int, int, int)
#>                ReturnType
#> 374                  real
#> 375 vector;array[] vector
#> 376                  real
#> 377                  real
#> 378 vector;array[] vector
#> 557                T;real
#> 558                T;real
#> 559                T;real
#> 560                T;real
#> 561                T;real
#> 562                T;real
#> 563                T;real
#> 564                T;real
lookup("^poisson") # every Stan function that starts with poisson
#>             StanFunction
#> 459     poisson_ccdf_log
#> 460          poisson_cdf
#> 461      poisson_cdf_log
#> 462        poisson_lccdf
#> 463         poisson_lcdf
#> 464          poisson_log
#> 465 poisson_log_glm_lpmf
#> 466      poisson_log_log
#> 467     poisson_log_lpmf
#> 468      poisson_log_rng
#> 469         poisson_lpmf
#> 470          poisson_rng
#>                                                     Arguments ReturnType
#> 459                                    (int, T);(int, vector)     T;real
#> 460                                    (int, T);(int, vector)     T;real
#> 461                                    (int, T);(int, vector)     T;real
#> 462                                    (int, T);(int, vector)     T;real
#> 463                                    (int, T);(int, vector)     T;real
#> 464                                    (int, T);(int, vector)     T;real
#> 465 (int, matrix, real, vector);(int, matrix, vector, vector)  real;real
#> 466                                    (int, T);(int, vector)     T;real
#> 467                                    (int, T);(int, vector)     T;real
#> 468                                                (T);(real)      T;int
#> 469                                    (int, T);(int, vector)     T;real
#> 470                                                (T);(real)      T;int