#ifndef _BACKPROP_H_
#define _BACKPROP_H_

#define BIGRND 0x7fffffff

#define GPU
#define THREADS 256
#define WIDTH 16  // shared memory width  
#define HEIGHT 16 // shared memory height

#define ETA 0.3       //eta value
#define MOMENTUM 0.3  //momentum value
#define NUM_THREAD 4  //OpenMP threads


typedef struct {
  int input_n;                  /* number of input units */
  int hidden_n;                 /* number of hidden units */
  int output_n;                 /* number of output units */

  float *input_units;          /* the input units */
  float *hidden_units;         /* the hidden units */
  float *output_units;         /* the output units */

  float *hidden_delta;         /* storage for hidden unit error */
  float *output_delta;         /* storage for output unit error */

  float *target;               /* storage for target vector */

  float **input_weights;       /* weights from input to hidden layer */
  float **hidden_weights;      /* weights from hidden to output layer */

                                /*** The next two are for momentum ***/
  float **input_prev_weights;  /* previous change on input to hidden wgt */
  float **hidden_prev_weights; /* previous change on hidden to output wgt */
} BPNN;


/*** User-level functions ***/

void bpnn_initialize();

BPNN *bpnn_create();
void bpnn_free();

void bpnn_train();
void bpnn_feedforward();

void bpnn_save();
BPNN *bpnn_read();


#endif