Interfacing D to C R standalone math library

[TJB]

Jacob,

Yep!  That did it. Thank you very much!

TJB

On Thursday, 31 May 2012 at 06:19:34 UTC, Jacob Carlborg wrote:
> On 2012-05-30 21:20, TJB wrote:
>> Hello!
>>
>> I am still wet behind the ears with D. I am trying to 
>> interface to an
>> existing C library from the R standalone math library
>> (www.r-project.org). I can call the library quite easily from 
>> a C++
>> program as follows:
>>
>>
>> #include <iostream>
>> #include <time.h>
>> #define MATHLIB_STANDALONE
>> #include "Rmath.h"
>>
>> using namespace std;
>>
>> int main() {
>> int i, n;
>> double sum, x;
>> time_t tt;
>>
>> tt = time(NULL);
>>
>> set_seed(tt, 77911);
>>
>> cout << "How many random normals to find the mean? ";
>> cin >> n;
>>
>> sum = 0.0;
>> for(i = 0; i < n; i++) {
>> sum += rnorm(0, 1);
>> }
>>
>> cout << "mean is " << sum/n << endl;
>>
>> return 0;
>> }
>>
>> I can compile this with:
>>
>> $ g++ -o rnorm rnorm.cpp -I /usr/include -L /usr/lib -lRmath 
>> -lm
>>
>> When I grep rnorm from the Rmath.h header file I get:
>>
>> $ grep rnorm Rmath.h
>> #define rnorm Rf_rnorm
>> double rnorm(double, double);
>>
>> I have written D code to call this as follows:
>>
>> import std.stdio;
>>
>> extern (C) double rnorm(double, double);
>>
>> void main() {
>> writeln(myfunc(0.0, 1.0));
>> }
>>
>> double myfunc(double a, double b) {
>> return rnorm(a, b);
>> }
>>
>> But I don't know what I need to do to compile it. What flags 
>> do I add?
>> What else do I have to do?
>>
>> Thanks for your help!
>>
>>
>
> You just need to link to the external libraries.
>
> $ dmd rnorm.d -L-L/usr/lib -L-lRmath -L-lm