Hi, I would like to know how to define a arbitrary mathematical
function with one variable and a list of paramter, like, f(x). For
example, in GSL library this is done as
/* Definition of an arbitrary function with parameters */
struct gsl_function_st ruct
{
double (* function) (double x, void * params);
void * params;
};
typedef struct gsl_function_st ruct gsl_function ;
#define GSL_FN_EVAL(F,x ) (*((F)->function))(x,( F)->params)
and the usage is here: http://www.gnu.org/software/gsl/manu...ction-to-solve
I wonder how one does it in C++?
Thanks. 2  2468  da*******@gmail .com wrote:
Hi, I would like to know how to define a arbitrary mathematical
double (* function) (double x, void * params);
http://www.gnu.org/software/gsl/manu...ction-to-solve
I wonder how one does it in C++?
If you're using gnu stuff anyway, "man stdarg" should do the trick (has
an example).
googling should tell you how to use it on different systems too. da*******@gmail .com wrote:
Hi, I would like to know how to define a arbitrary mathematical
function with one variable and a list of paramter, like, f(x). For
example, in GSL library this is done as
/* Definition of an arbitrary function with parameters */
struct gsl_function_st ruct
{
double (* function) (double x, void * params);
void * params;
};
typedef struct gsl_function_st ruct gsl_function ;
#define GSL_FN_EVAL(F,x ) (*((F)->function))(x,( F)->params)
and the usage is here:
http://www.gnu.org/software/gsl/manu...ction-to-solve
I wonder how one does it in C++?
In C++, one would use a functor. See this for a description: http://www.sgi.com/tech/stl/functors.html
See especially the example involving struct less_mag.
Cheers! --M This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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