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model_squarewave_ap.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_squarewave_ap.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 square wave model -----*/   
00050 
00051   /*----- name of this model -----*/
00052   strcpy (mi->label, "SquareWave_AP");
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 = 2;
00059 
00060   /*----- parameter labels -----*/
00061   strcpy (mi->plabel[0], "amplitude");
00062   strcpy (mi->plabel[1], "phase");
00063 
00064   /*----- minimum and maximum parameter constraints -----*/
00065   mi->min_constr[0] =   -100.0;    mi->max_constr[0] =   100.0;
00066   mi->min_constr[1] =    -90.0;    mi->max_constr[1] =     0.00;
00067   
00068   /*----- function which implements the model -----*/
00069   mi->call_func = &signal_model;
00070 
00071 
00072   /*----- return pointer to the model interface -----*/
00073   return (mi);
00074 }

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

Definition at line 89 of file model_squarewave_ap.c.

Referenced by initialize_model().

00096 {
00097   const float FREQ = 0.125;         /* frequency of the square wave */
00098   int it;                           /* time index */     
00099   float t;                          /* time */
00100   float fval;                       /* time series value at time t */  
00101 
00102 
00103   /*----- calculate time series corresponding to the given parameters -----*/
00104   for (it = 0;  it < ts_length;  it++)
00105     { 
00106       t = x_array[it][1];
00107       fval = sin (2.0*PI*FREQ*t + (PI/180.0)*gs[1]);
00108       if (fval >= 0.0)
00109         fval = gs[0];
00110       else
00111         fval = -gs[0];
00112       ts_array[it] = fval;      
00113     }
00114   
00115 }
 

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