just sharing/archiving.
fortran wrapper:
! lapdog.so
! f95 -shared -o lapdog.so types.o constants.o utils.o lapack.o linalg.o
lapdog.o -llapack
module lapdog
use linalg, only: solve ! https://github.com/certik/fortran-utils
use iso_c_binding, only: c_int, c_double
implicit none
contains
subroutine solver(n,a,b,x) bind(c)
integer(c_int), intent(in) :: n
real(c_double), intent(in) :: a(n,n)
real(c_double), intent(in) :: b(n)
real(c_double), intent(out) :: x(n)
x = solve(a,b)
end subroutine solver
end module lapdog
nim test program:
# test.nim
# nim c test.nim
const
N = 3
type
m1 = array[1..N, float64]
m2 = array[1..N, m1]
proc solver(n: ptr int; a: m2; b: m1; x: var m1)
{. dynlib: "./lapdog.so", importc .}
when isMainModule:
# solve for x, y, z where:
# 1) 1x + 1y − 1z = 4
# 2) 1x − 2y + 3z = −6
# 3) 2x + 3y + 1z = 7
var
n: int = N
A: m2
B: m1
X: m1
A[1][1] = 1
A[1][2] = 1
A[1][3] = 2
A[2][1] = 1
A[2][2] = -2
A[2][3] = 3
A[3][1] = -1
A[3][2] = 3
A[3][3] = 1
B[1] = 4
B[2] = -6
B[3] = 7
solver(n.addr(),A,B,X)
for i in 1..N:
echo X[i]
