c++ - Conversion function from std::bind -


i receiving error when create new function using std::bind , trying pass function.

my code looks like

#include <functional> using namespace std; typedef double (*t_function)(double t, double *y);  double integrate_fmax(double s, bool(*t_max)(double t, double *y), void(*fce_min)(double s, double &t_0, double *y_0), t_function fce_max, double err, t_function *f_diff, int dim){...}  void get_x1_x2(double &x1, double &x2, double(*fce)(double x), double mlt){...}  double shoot_meth(double s1, double mlt, bool(*t_max)(double t, double *y), void(*fce_min)(double s, double &t_0, double *y_0), t_function fce_max, double err, t_function *f_diff, int dim){     double s2;       auto fce_x = bind(integrate_fmax, placeholders::_1, t_max, fce_min, fce_max, err, f_diff, dim);     get_x1_x2(s1, s2, fce_x, mlt); }

i receving error when try pass function fce_x get_x1_x2:

c2664: 'void get_x1_x2(double &,double &,double (__cdecl *)(double),double)' : cannot convert argument 3 'std::_bind<true,double,double (__cdecl *const )(double,bool (__cdecl *)(double,double *),void (__cdecl *)(double,double &,double *),t_function,double,t_function *,int),std::_ph<1> &,bool (__cdecl *&)(double,double *),void (__cdecl *&)(double,double &,double *),double (__cdecl *&)(double,double *),double &,t_function *&,int &>' 'double (__cdecl *)(double)'

but when tried double foo = fce_x(5) no error.

i using microsoft visual studio 2013.

p.s. sorry ugly functions not sure error , simplifying help.

std::bind not return function pointer. need use std::function instead. because std::bind guaranteed return can stored in std::function. if replace

double(*fce)(double x)

with

std::function<double(double)> fce

it should work properly.


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