I want to learn more R+Fortran so I created this package to play with R+Fortran
ALWAYS READ THE R-EXTS MANUAL
Comparison R and Fortran
(TODO Move to wiki or vignette)
ma <- array(1:6, c(3,2))
dim(ma) # shape in fortran
#> [1] 3 2
length(ma) # size in fortran
#> [1] 6
nrow(ma) # size(ma, 1)
#> [1] 3
ncol(ma) # size(ma, 2)
#> [1] 2
length(dim(ma)) # rank ma
#> [1] 2
print(ma)
#> [,1] [,2]
#> [1,] 1 4
#> [2,] 2 5
#> [3,] 3 6
library(inline)
code <- "
real, dimension(3,2) :: a
print *, 'size of a: ', size(a)
print *, 'size of 1 dim a : ', size(a,1)
print *, 'size of 2 dim a : ',size(a,2)
print *, 'rank a: ', rank(a)
print *, 'shape a: ', shape(a)
"
cubefn <- cfunction(body = code, convention=".Fortran")
print(cubefn)
#> An object of class 'CFunc'
#> function ()
#> .Primitive(".Fortran")(<pointer: 0x7f9a1dc07150>)
#> <environment: 0x56428c50fc10>
#> code:
#> 1:
#> 2: SUBROUTINE file312f6a470742 ( )
#> 3:
#> 4:
#> 5: real, dimension(3,2) :: a
#> 6: print *, 'size of a: ', size(a)
#> 7: print *, 'size of 1 dim a : ', size(a,1)
#> 8: print *, 'size of 2 dim a : ',size(a,2)
#> 9: print *, 'rank a: ', rank(a)
#> 10: print *, 'shape a: ', shape(a)
#> 11:
#> 12: RETURN
#> 13: END
#> 14:
cubefn()
#> list()Implementing several new fortran subroutines
I’ve found a nice repo AstroFrog with lots of fortran subroutines that I will implementing as R functions here. The implementation in R is vectorial, hence in Fortra arrays with the required dimension.
| id | Fortran | R |
|---|---|---|
| 1 | OpenMP | get_threads |
| 2 | base_types.f90 | get_types |
| 3 | lib_algebra.f90 | quadratic_reduced |
| 4 | lib_algebra.f90 | quadratic |
| 5 | lib_algebra.f90 | cbrt |
library(rfortran)
get_threads()
#> [1] 12
cbrt(1:3)
#> [1] 1.000000 1.259921 1.442250
dp_quadratic_reduced(1:4,4:1)
#> x1 x2 delta delta_positive
#> 1 1.797693e+308 1.797693e+308 -15.000000 FALSE
#> 2 1.797693e+308 1.797693e+308 -8.000000 FALSE
#> 3 -2.000000e+00 -1.000000e+00 1.000000 TRUE
#> 4 -3.732051e+00 -2.679492e-01 3.464102 TRUE
dp_quadratic(1:4,4:1,4:1)
#> x1 x2 a delta delta_positive
#> 1 1.797693e+308 1.797693e+308 4 0 FALSE
#> 2 1.797693e+308 1.797693e+308 3 0 FALSE
#> 3 1.797693e+308 1.797693e+308 2 0 FALSE
#> 4 -3.732051e+00 -2.679492e-01 1 0 FALSE
dp_quadratic_pascal(1:4,4:1,4:1)
#> x1 x2 a delta delta_positive
#> 1 -1.797693e+308 -1.797693e+308 4 0 FALSE
#> 2 -1.797693e+308 -1.797693e+308 3 0 FALSE
#> 3 -1.797693e+308 -1.797693e+308 2 0 FALSE
#> 4 -3.732051e+00 -2.679492e-01 1 0 FALSEAdd more
If you know any play, fortran subroutine, trick or anything let me know, make a pull request or anything
