Re: Any good package for mathematical function in Ada?

["Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>]

On 01/06/2020 10:24, reinert wrote:

> Anybody having a simple (complete - runable) code example using GSL from Ada?

Assuming Windows.

Install MSYS2 if you did not already. [64-bit, GNAT GPL is not available 
for 32-bit anymore.]

Install GSL mingw-w64-x86_64-gsl under MSYS.

Now, assuming that MSYS2 is under C:\MSYS64\MinGW, here you go:

---gsl.gpr--------------
project GSL is
    for Main use ("test.adb");

    package Linker is
       for Default_Switches ("ada")
          use ("-L/c/msys64/mingw/lib", "-lgsl");
    end Linker;

end GSL;

---gsl.ads-------------
with Interfaces.C;  use Interfaces.C;

package GSL is
   function Bessel_J0 (X : double) return double;

private
    pragma Import (C, Bessel_J0, "gsl_sf_bessel_J0");
end GSL;

---test.adb------------>
with Ada.Text_IO;   use Ada.Text_IO;
with GSL;           use GSL;
with Interfaces.C;  use Interfaces.C;

procedure Test is
begin
    Put_Line ("J0(1)=" & double'Image (Bessel_J0 (1.0)));
end Test;
-----------------------

The test produces:

J0(1)= 7.65197686557967E-01

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de