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model_beta.c File Reference

#include <math.h>
#include "NLfit_model.h"

Go to the source code of this file.


Functions

void signal_model (float *gs, int ts_length, float **x_array, float *ts_array)
DEFINE_MODEL_PROTOTYPE MODEL_interfaceinitialize_model ()

Function Documentation

DEFINE_MODEL_PROTOTYPE MODEL_interface* initialize_model  
 

Definition at line 40 of file model_beta.c.

References MODEL_interface::call_func, MODEL_interface::label, MODEL_interface::max_constr, MODEL_interface::min_constr, MODEL_SIGNAL_TYPE, MODEL_interface::model_type, MODEL_interface::params, MODEL_interface::plabel, signal_model(), and XtMalloc.

00041 {
00042   MODEL_interface * mi = NULL;
00043 
00044 
00045   /*----- allocate memory space for model interface -----*/
00046   mi = (MODEL_interface *) XtMalloc (sizeof(MODEL_interface));
00047 
00048 
00049   /*----- define interface for the differential - exponential model -----*/   
00050 
00051   /*----- name of this model -----*/
00052   strcpy (mi->label, "Beta");
00053 
00054   /*----- this is a signal model -----*/
00055   mi->model_type = MODEL_SIGNAL_TYPE;
00056 
00057   /*----- number of parameters in the model -----*/
00058   mi->params = 5;
00059 
00060   /*----- parameter labels -----*/
00061   strcpy (mi->plabel[0], "t0");
00062   strcpy (mi->plabel[1], "tf");
00063   strcpy (mi->plabel[2], "k");
00064   strcpy (mi->plabel[3], "alpha");
00065   strcpy (mi->plabel[4], "beta");
00066 
00067   /*----- minimum and maximum parameter constraints -----*/
00068   mi->min_constr[0] =    27.0;    mi->max_constr[0] =    77.0;
00069   mi->min_constr[1] =    78.0;    mi->max_constr[1] =   250.0;
00070   mi->min_constr[2] = -5000.0;    mi->max_constr[2] =  5000.0;
00071   mi->min_constr[3] =    0.00;    mi->max_constr[3] =    10.0;
00072   mi->min_constr[4] =    0.00;    mi->max_constr[4] =    10.0;
00073   
00074   /*----- function which implements the model -----*/
00075   mi->call_func = &signal_model;
00076 
00077 
00078   /*----- return pointer to the model interface -----*/
00079   return (mi);
00080 }

void signal_model float *    gs,
int    ts_length,
float **    x_array,
float *    ts_array
 

Definition at line 99 of file model_beta.c.

Referenced by initialize_model().

00106 {
00107   int it;                           /* time index */     
00108   float t;                          /* time */
00109   float fval;                       /* time series value at time t */  
00110   float x;                          /* rescaled t */
00111   float t0, tf, k, alpha, beta;     /* parameters */
00112 
00113 
00114   t0 = gs[0];
00115   tf = gs[1];
00116   k  = gs[2];
00117   alpha = gs[3];
00118   beta  = gs[4];
00119 
00120   for (it = 0;  it < ts_length;  it++)
00121     {
00122       t = x_array[it][1];
00123       if ((t <= t0) || (t >= tf) || (t0 >= tf))
00124         fval = 0.0;
00125       else
00126         {
00127           x = (t - t0) / (tf - t0);
00128           fval = k * exp((alpha-1.0)*log(x)) * exp((beta-1.0)*log(1.0-x));
00129         }
00130       ts_array[it] = fval;
00131     }
00132 }
 

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