#include <origin.h>
// Add your special include files here.
// For example, if you want to fit with functions from the NAG library, 
// add the header file for the NAG functions here.
#include <oc_nag8.h>
 
 
// Add code here for other Origin C functions that you want to define in this file,
// and access in your fitting function.
struct user
{
	double a, b, fitX;  // fitX the independent variable of fitting function
 
};
static double NAG_CALL f_callback(double x, Nag_User *comm)  // x is the independent variable of the integrand
{
 
	struct user *sp = (struct user *)(comm->p);
 
        double aa, bb, fitX; // temp variable to accept the parameters in the Nag_User communication struct
        aa = sp->a;
        bb = sp->b;
        fitX = sp->fitX;
 
        return exp(fitX/(0.8))*exp(-bb/(8.314*fitX))*exp((-aa*8.314*fitX*fitX*exp(-bb/(8.314*fitX)))/(0.4*bb));
}
 
// You can access C functions defined in other files, if those files are loaded and compiled 
// in your workspace, and the functions have been prototyped in a header file that you have
// included above. 
 
// You can access NLSF object methods and properties directly in your function code.
 
// You should follow C-language syntax in defining your function. 
// For instance, if your parameter name is P1, you cannot use p1 in your function code. 
// When using fractions, remember that integer division such as 1/2 is equal to 0, and not 0.5
// Use 0.5 or 1/2.0 to get the correct value.
 
// For more information and examples, please refer to the "User-Defined Fitting Function" 
// section of the Origin Help file.

// 

//----------------------------------------------------------
// 
void _nlsfPWwithparametric(
// Fit Parameter(s):
double a, double b, double c, double d,
// Independent Variable(s):
double x,
// Dependent Variable(s):
double& y)
{
	// Beginning of editable part
	double epsabs = 0.00001, epsrel = 0.0000001, result, abserr;
	Integer max_num_subint = 500;  
	        // you may use epsabs and epsrel and this quantity to enhance your desired precision 
	        // when not enough precision encountered
	 
	Nag_QuadProgress qp;
	static NagError fail;
	 
	// the parameters parameterize the integrand can be input to the call_back function
	        // through the Nag_User communication struct 
	        Nag_User comm;	
	struct user s;
	s.a = a;
	s.b = b;
	s.fitX = x;
	        comm.p = (Pointer)&s;
	 
	d01sjc(f_callback, c, s.fitX, epsabs, epsrel, max_num_subint, &result, &abserr, &qp, &comm, &fail);
	 
	 
	        // you may want to exam the error by printing out error message, just uncomment the following lines
	// if (fail.code != NE_NOERROR)
	        // printf("%s\n", fail.message);
	 
	 
	// For the error other than the following three errors which are due to bad input parameters 
	// or allocation failure  NE_INT_ARG_LT  NE_BAD_PARAM   NE_ALLOC_FAIL
	// You will need to free the memory allocation before calling the integration routine again to 
	        // avoid memory leakage
	if (fail.code != NE_INT_ARG_LT && fail.code != NE_BAD_PARAM && fail.code != NE_ALLOC_FAIL)
	{
		NAG_FREE(qp.sub_int_beg_pts);
		NAG_FREE(qp.sub_int_end_pts);
		NAG_FREE(qp.sub_int_result);
		NAG_FREE(qp.sub_int_error);
	}
	 
	 
	y = d*(exp(-x/0.8))*(a/0.4)*result; 
	// End of editable part
}

#include <origin.h>
// Add your special include files here.
// For example, if you want to fit with functions from the NAG library, 
// add the header file for the NAG functions here.
#include <oc_nag8.h>
 
 
// Add code here for other Origin C functions that you want to define in this file,
// and access in your fitting function.
 
struct user   // parameters in the integrand
{
	double amp, center, width;
 
};
// Function supplied by user, return the value of the integrand at a given x.
static double NAG_CALL f_callback(double x, Nag_User *comm) 
{
        struct user *sp = (struct user *)(comm->p);
 
        double amp, center, width;    // temp variable to accept the parameters in the Nag_User communication struct
        amp = sp->amp;
        center = sp->center;
        width = sp->width;
 
	return amp * exp(x/(0.8))*exp(-center/(8.314*x))*exp((-width*8.314*x*x*exp(-center/(8.314*x)))/(0.4*center));
}
 
 
// You can access C functions defined in other files, if those files are loaded and compiled 
// in your workspace, and the functions have been prototyped in a header file that you have
// included above. 
 
// You can access NLSF object methods and properties directly in your function code.
 
// You should follow C-language syntax in defining your function. 
// For instance, if your parameter name is P1, you cannot use p1 in your function code. 
// When using fractions, remember that integer division such as 1/2 is equal to 0, and not 0.5
// Use 0.5 or 1/2.0 to get the correct value.
 
// For more information and examples, please refer to the "User-Defined Fitting Function" 
// section of the Origin Help file.


//----------------------------------------------------------
// 
void _nlsfPW(
// Fit Parameter(s):
double y0, double A, double xc, double w,
// Independent Variable(s):
double x,
// Dependent Variable(s):
double& y)
{
	// Beginning of editable part
	// Through the absolute accuracy epsabs, relative accuracy epsrel and max_num_subint you can  
	// control the precision of the integration you need 
	// if epsrel is set negative, the absolute accuracy will be used. 
	// Similarly, you can control only relative accuracy by set the epsabs negative
	double epsabs = 0.0, epsrel = 0.0001;
	 
	// The max number of sub-intervals needed to evaluate the function in the integral
	// The more diffcult the integrand the larger max_num_subint should be
	// For most problems 200 to 500 is adequate and recommmended
	Integer max_num_subint = 200;
	 
	// Result keeps the approximate integral value returned by the algorithm
	// abserr is an estimate of the error which should be an upper bound for the |I - result| 
	// where I is the integral value
	double result, abserr;
	 
	// The structure of type Nag_QuadProgress, 
	// it contains pointers allocated memory internally with max_num_subint elements
	Nag_QuadProgress qp;
	 
	// The NAG error parameter (structure)
	static NagError fail;
	 
	// Parameters passed to integrand by Nag_User communication struct
	        Nag_User comm;	
	struct user s;
	        s.amp = A;
	        s.center = xc;
	        s.width = w;
	        comm.p = (Pointer)&s;
	 
	// Perform integration
	// There are 3 kinds of infinite boundary types you can use in Nag infinite integrator
	// Nag_LowerSemiInfinite, Nag_UpperSemiInfinite, Nag_Infinite
	d01smc(f_callback, Nag_LowerSemiInfinite, x, epsabs, epsrel, max_num_subint, &result, &abserr, &qp, &comm, &fail);
	 
	        // you may want to exam the error by printing out error message, just uncomment the following lines
	// if (fail.code != NE_NOERROR)
	      //  printf("%s\n", fail.message);
	 
	// For the error other than the following three errors which are due to bad input parameters 
	// or allocation failure  NE_INT_ARG_LT  NE_BAD_PARAM   NE_ALLOC_FAIL
	// You will need to free the memory allocation before calling the integration routine again to avoid memory leakage
	if (fail.code != NE_INT_ARG_LT && fail.code != NE_BAD_PARAM && fail.code != NE_ALLOC_FAIL)
	{
		NAG_FREE(qp.sub_int_beg_pts);
		NAG_FREE(qp.sub_int_end_pts);
		NAG_FREE(qp.sub_int_result);
		NAG_FREE(qp.sub_int_error);
	}
	 
	// Calculate the fitted value
	y = y0 + exp(-x/0.8)*w/0.4*result;
	// End of editable part
}