path: root/neural.c

#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <stdbool.h>
#include <string.h>
#include <math.h>
#include <limits.h>
#include <time.h>

#include "cleanbench.h"
#include "randnum.h"


/********************************
** BACK PROPAGATION NEURAL NET **
*********************************
** This code is a modified version of the code
** that was submitted to BYTE Magazine by
** Maureen Caudill.  It accomanied an article
** that I CANNOT NOW RECALL.
** The author's original heading/comment was
** as follows:
**
**  Backpropagation Network
**  Written by Maureen Caudill
**  in Think C 4.0 on a Macintosh
**
**  (c) Maureen Caudill 1988-1991
**  This network will accept 5x7 input patterns
**  and produce 8 bit output patterns.
**  The source code may be copied or modified without restriction,
**  but no fee may be charged for its use.
**
** ++++++++++++++
** I have modified the code so that it will work
** on systems other than a Macintosh -- RG
*/

/*
**  LOOP_MAX
**
** This constant sets the max number of loops through the neural
** net that the system will attempt before giving up.  This
** is not a critical constant.  You can alter it if your system
** has sufficient horsepower.
*/
#define LOOP_MAX  500000L

#define ERR -1
#define MAXPATS 10              /* max number of patterns in data file */
#define IN_X_SIZE 5             /* number of neurodes/row of input layer */
#define IN_Y_SIZE 7             /* number of neurodes/col of input layer */
#define IN_SIZE 35              /* equals IN_X_SIZE*IN_Y_SIZE */
#define MID_SIZE 8              /* number of neurodes in middle layer */
#define OUT_SIZE 8              /* number of neurodes in output layer */
#define MARGIN 0.1              /* how near to 1,0 do we have to come to stop? */
#define BETA 0.09               /* beta learning constant */
#define ALPHA 0.09              /* momentum term constant */
#define STOP 0.1                /* when worst_error less than STOP, training is done */

double  mid_wts[MID_SIZE][IN_SIZE];     /* middle layer weights */
double  out_wts[OUT_SIZE][MID_SIZE];    /* output layer weights */
double  mid_out[MID_SIZE];              /* middle layer output */
double  out_out[OUT_SIZE];              /* output layer output */
double  mid_error[MID_SIZE];            /* middle layer errors */
double  out_error[OUT_SIZE];            /* output layer errors */
double  mid_wt_change[MID_SIZE][IN_SIZE]; /* storage for last wt change */
double  out_wt_change[OUT_SIZE][MID_SIZE]; /* storage for last wt change */
double  in_pats[MAXPATS][IN_SIZE];      /* input patterns */
double  out_pats[MAXPATS][OUT_SIZE];    /* desired output patterns */
double  tot_out_error[MAXPATS];         /* measure of whether net is done */
double  out_wt_cum_change[OUT_SIZE][MID_SIZE]; /* accumulated wt changes */
double  mid_wt_cum_change[MID_SIZE][IN_SIZE];  /* accumulated wt changes */

double  worst_error; /* worst error each pass through the data */
double  average_error; /* average error each pass through the data */
double  avg_out_error[MAXPATS]; /* average error each pattern */

int iteration_count;    /* number of passes thru network so far */
int numpats;            /* number of patterns in data file */
int numpasses;          /* number of training passes through data file */
int learned;            /* flag--if true, network has learned all patterns */

static clock_t DoNNetIteration(unsigned long nloops);
static void do_mid_forward(int patt);
static void do_out_forward();
static void do_forward_pass(int patt);
static void do_out_error(int patt);
static void worst_pass_error();
static void do_mid_error();
static void adjust_out_wts();
static void adjust_mid_wts();
static void do_back_pass(int patt);
static void move_wt_changes();
static int check_out_error();
static void zero_changes();
static void randomize_wts();
static int read_data_file();

/***********
** DoNNet **
************
** Perform the neural net benchmark.
** Note that this benchmark is one of the few that
** requires an input file.  That file is "NNET.DAT" and
** should be on the local directory (from which the
** benchmark program in launched).
*/
double
DoNNET(void)
{
        clock_t         total_time = 0;
        int             iterations = 0;
        static bool     is_adjusted = false;
        static int      loops = 0;

        /*
        ** Init random number generator.
        ** NOTE: It is important that the random number generator
        **  be re-initialized for every pass through this test.
        **  The NNET algorithm uses the random number generator
        **  to initialize the net.  Results are sensitive to
        **  the initial neural net state.
        */
        randnum((int32_t)3);

        /*
        ** Read in the input and output patterns.  We'll do this
        ** only once here at the beginning.  These values don't
        ** change once loaded.
        */
        if(read_data_file()!=0) {
                exit(1);
        }

        /*
        ** See if we need to perform self adjustment loop.
        */
        if (is_adjusted == false) {
                is_adjusted = true;
                /*
                ** Do self-adjustment.  This involves initializing the
                ** # of loops and increasing the loop count until we
                ** get a number of loops that we can use.
                */
                do {
                        randnum(3);
                        ++loops;
                } while ((DoNNetIteration(loops) <= MINIMUM_TICKS) && (loops < LOOP_MAX));
        }

        do {
                randnum((int32_t)3);    /* Gotta do this for Neural Net */
                total_time += DoNNetIteration(loops);
                iterations += loops;
        } while (total_time < MINIMUM_SECONDS * CLOCKS_PER_SEC);

        return (double)(iterations * CLOCKS_PER_SEC) / total_time;
}

/********************
** DoNNetIteration **
*********************
** Do a single iteration of the neural net benchmark.
** By iteration, we mean a "learning" pass.
*/
static clock_t
DoNNetIteration(unsigned long nloops)
{
        clock_t start, stop;
int patt;

/*
** Run nloops learning cycles.  Notice that, counted with
** the learning cycle is the weight randomization and
** zeroing of changes.  This should reduce clock jitter,
** since we don't have to stop and start the clock for
** each iteration.
*/
        start = clock();
while(nloops--)
{
	randomize_wts();
	zero_changes();
	iteration_count=1;
	learned = false;
	numpasses = 0;
	while (!learned)
	{
		for (patt=0; patt<numpats; patt++)
		{
			worst_error = 0.0;      /* reset this every pass through data */
			move_wt_changes();      /* move last pass's wt changes to momentum array */
			do_forward_pass(patt);
			do_back_pass(patt);
			iteration_count++;
		}
		numpasses ++;
		learned = check_out_error();
	}
}
        stop = clock();

        return stop - start;
}

/*************************
** do_mid_forward(patt) **
**************************
** Process the middle layer's forward pass
** The activation of middle layer's neurode is the weighted
** sum of the inputs from the input pattern, with sigmoid
** function applied to the inputs.
**/
static void  do_mid_forward(int patt)
{
double  sum;
int     neurode, i;

for (neurode=0;neurode<MID_SIZE; neurode++)
{
	sum = 0.0;
	for (i=0; i<IN_SIZE; i++)
	{       /* compute weighted sum of input signals */
		sum += mid_wts[neurode][i]*in_pats[patt][i];
	}
	/*
	** apply sigmoid function f(x) = 1/(1+exp(-x)) to weighted sum
	*/
	sum = 1.0/(1.0+exp(-sum));
	mid_out[neurode] = sum;
}
return;
}

/*********************
** do_out_forward() **
**********************
** process the forward pass through the output layer
** The activation of the output layer is the weighted sum of
** the inputs (outputs from middle layer), modified by the
** sigmoid function.
**/
static void  do_out_forward()
{
double sum;
int neurode, i;

for (neurode=0; neurode<OUT_SIZE; neurode++)
{
	sum = 0.0;
	for (i=0; i<MID_SIZE; i++)
	{       /*
		** compute weighted sum of input signals
		** from middle layer
		*/
		sum += out_wts[neurode][i]*mid_out[i];
	}
	/*
	** Apply f(x) = 1/(1+exp(-x)) to weighted input
	*/
	sum = 1.0/(1.0+exp(-sum));
	out_out[neurode] = sum;
}
}

/**********************
** do_forward_pass() **
***********************
** control function for the forward pass through the network
**/
static void  do_forward_pass(int patt)
{
do_mid_forward(patt);   /* process forward pass, middle layer */
do_out_forward();       /* process forward pass, output layer */
}

/***********************
** do_out_error(patt) **
************************
** Compute the error for the output layer neurodes.
** This is simply Desired - Actual.
**/
static void do_out_error(int patt)
{
int neurode;
double error,tot_error, sum;

tot_error = 0.0;
sum = 0.0;
for (neurode=0; neurode<OUT_SIZE; neurode++)
{
	out_error[neurode] = out_pats[patt][neurode] - out_out[neurode];
	/*
	** while we're here, also compute magnitude
	** of total error and worst error in this pass.
	** We use these to decide if we are done yet.
	*/
	error = out_error[neurode];
	if (error <0.0)
	{
		sum += -error;
		if (-error > tot_error)
			tot_error = -error; /* worst error this pattern */
	}
	else
	{
		sum += error;
		if (error > tot_error)
			tot_error = error; /* worst error this pattern */
	}
}
avg_out_error[patt] = sum/OUT_SIZE;
tot_out_error[patt] = tot_error;
return;
}

/***********************
** worst_pass_error() **
************************
** Find the worst and average error in the pass and save it
**/
static void  worst_pass_error()
{
double error,sum;

int i;

error = 0.0;
sum = 0.0;
for (i=0; i<numpats; i++)
{
	if (tot_out_error[i] > error) error = tot_out_error[i];
	sum += avg_out_error[i];
}
worst_error = error;
average_error = sum/numpats;
return;
}

/*******************
** do_mid_error() **
********************
** Compute the error for the middle layer neurodes
** This is based on the output errors computed above.
** Note that the derivative of the sigmoid f(x) is
**        f'(x) = f(x)(1 - f(x))
** Recall that f(x) is merely the output of the middle
** layer neurode on the forward pass.
**/
static void do_mid_error()
{
double sum;
int neurode, i;

for (neurode=0; neurode<MID_SIZE; neurode++)
{
	sum = 0.0;
	for (i=0; i<OUT_SIZE; i++)
		sum += out_wts[i][neurode]*out_error[i];

	/*
	** apply the derivative of the sigmoid here
	** Because of the choice of sigmoid f(I), the derivative
	** of the sigmoid is f'(I) = f(I)(1 - f(I))
	*/
	mid_error[neurode] = mid_out[neurode]*(1-mid_out[neurode])*sum;
}
return;
}

/*********************
** adjust_out_wts() **
**********************
** Adjust the weights of the output layer.  The error for
** the output layer has been previously propagated back to
** the middle layer.
** Use the Delta Rule with momentum term to adjust the weights.
**/
static void adjust_out_wts()
{
int weight, neurode;
double learn,delta,alph;

learn = BETA;
alph  = ALPHA;
for (neurode=0; neurode<OUT_SIZE; neurode++)
{
	for (weight=0; weight<MID_SIZE; weight++)
	{
		/* standard delta rule */
		delta = learn * out_error[neurode] * mid_out[weight];

		/* now the momentum term */
		delta += alph * out_wt_change[neurode][weight];
		out_wts[neurode][weight] += delta;

		/* keep track of this pass's cum wt changes for next pass's momentum */
		out_wt_cum_change[neurode][weight] += delta;
	}
}
return;
}

/*************************
** adjust_mid_wts(patt) **
**************************
** Adjust the middle layer weights using the previously computed
** errors.
** We use the Generalized Delta Rule with momentum term
**/
static void adjust_mid_wts(int patt)
{
int weight, neurode;
double learn,alph,delta;

learn = BETA;
alph  = ALPHA;
for (neurode=0; neurode<MID_SIZE; neurode++)
{
	for (weight=0; weight<IN_SIZE; weight++)
	{
		/* first the basic delta rule */
		delta = learn * mid_error[neurode] * in_pats[patt][weight];

		/* with the momentum term */
		delta += alph * mid_wt_change[neurode][weight];
		mid_wts[neurode][weight] += delta;

		/* keep track of this pass's cum wt changes for next pass's momentum */
		mid_wt_cum_change[neurode][weight] += delta;
	}
}
return;
}

/*******************
** do_back_pass() **
********************
** Process the backward propagation of error through network.
**/
void  do_back_pass(int patt)
{

do_out_error(patt);
do_mid_error();
adjust_out_wts();
adjust_mid_wts(patt);

return;
}


/**********************
** move_wt_changes() **
***********************
** Move the weight changes accumulated last pass into the wt-change
** array for use by the momentum term in this pass. Also zero out
** the accumulating arrays after the move.
**/
static void move_wt_changes()
{
int i,j;

for (i = 0; i<MID_SIZE; i++)
	for (j = 0; j<IN_SIZE; j++)
	{
		mid_wt_change[i][j] = mid_wt_cum_change[i][j];
		/*
		** Zero it out for next pass accumulation.
		*/
		mid_wt_cum_change[i][j] = 0.0;
	}

for (i = 0; i<OUT_SIZE; i++)
	for (j=0; j<MID_SIZE; j++)
	{
		out_wt_change[i][j] = out_wt_cum_change[i][j];
		out_wt_cum_change[i][j] = 0.0;
	}

return;
}

/**********************
** check_out_error() **
***********************
** Check to see if the error in the output layer is below
** MARGIN*OUT_SIZE for all output patterns.  If so, then
** assume the network has learned acceptably well.  This
** is simply an arbitrary measure of how well the network
** has learned -- many other standards are possible.
**/
static int check_out_error()
{
int result,i,error;

result  = true;
error   = false;
worst_pass_error();     /* identify the worst error in this pass */

/*
#ifdef DEBUG
printf("\n Iteration # %d",iteration_count);
#endif
*/
for (i=0; i<numpats; i++)
{
/*      printf("\n Error pattern %d:   Worst: %8.3f; Average: %8.3f",
	  i+1,tot_out_error[i], avg_out_error[i]);
	fprintf(outfile,
	 "\n Error pattern %d:   Worst: %8.3f; Average: %8.3f",
	 i+1,tot_out_error[i]);
*/

	if (worst_error >= STOP) result = false;
	if (tot_out_error[i] >= 16.0) error = true;
}

if (error) result = ERR;


#ifdef DEBUG
/* printf("\n Error this pass thru data:   Worst: %8.3f; Average: %8.3f",
 worst_error,average_error);
*/
/* fprintf(outfile,
 "\n Error this pass thru data:   Worst: %8.3f; Average: %8.3f",
  worst_error, average_error); */
#endif

return(result);
}


/*******************
** zero_changes() **
********************
** Zero out all the wt change arrays
**/
static void zero_changes()
{
int i,j;

for (i = 0; i<MID_SIZE; i++)
{
	for (j=0; j<IN_SIZE; j++)
	{
		mid_wt_change[i][j] = 0.0;
		mid_wt_cum_change[i][j] = 0.0;
	}
}

for (i = 0; i< OUT_SIZE; i++)
{
	for (j=0; j<MID_SIZE; j++)
	{
		out_wt_change[i][j] = 0.0;
		out_wt_cum_change[i][j] = 0.0;
	}
}
return;
}


/********************
** randomize_wts() **
*********************
** Intialize the weights in the middle and output layers to
** random values between -0.25..+0.25
** Function rand() returns a value between 0 and 32767.
**
** NOTE: Had to make alterations to how the random numbers were
** created.  -- RG.
**/
static void randomize_wts()
{
int neurode,i;
double value;

/*
** Following not used int benchmark version -- RG
**
**        printf("\n Please enter a random number seed (1..32767):  ");
**        scanf("%d", &i);
**        srand(i);
*/

for (neurode = 0; neurode<MID_SIZE; neurode++)
{
	for(i=0; i<IN_SIZE; i++)
	{
	        /* value=(double)abs_randwc(100000L); */
		value=(double)abs_randwc((int32_t)100000);
		value=value/(double)100000.0 - (double) 0.5;
		mid_wts[neurode][i] = value/2;
	}
}
for (neurode=0; neurode<OUT_SIZE; neurode++)
{
	for(i=0; i<MID_SIZE; i++)
	{
	        /* value=(double)abs_randwc(100000L); */
		value=(double)abs_randwc((int32_t)100000);
		value=value/(double)10000.0 - (double) 0.5;
		out_wts[neurode][i] = value/2;
	}
}

return;
}


/*********************
** read_data_file() **
**********************
** Read in the input data file and store the patterns in
** in_pats and out_pats.
** The format for the data file is as follows:
**
** line#   data expected
** -----   ------------------------------
** 1               In-X-size,in-y-size,out-size
** 2               number of patterns in file
** 3               1st X row of 1st input pattern
** 4..             following rows of 1st input pattern pattern
**                 in-x+2  y-out pattern
**                                 1st X row of 2nd pattern
**                 etc.
**
** Each row of data is separated by commas or spaces.
** The data is expected to be ascii text corresponding to
** either a +1 or a 0.
**
** Sample input for a 1-pattern file (The comments to the
** right may NOT be in the file unless more sophisticated
** parsing of the input is done.):
**
** 5,7,8                      input is 5x7 grid, output is 8 bits
** 1                          one pattern in file
** 0,1,1,1,0                  beginning of pattern for "O"
** 1,0,0,0,1
** 1,0,0,0,1
** 1,0,0,0,1
** 1,0,0,0,1
** 1,0,0,0,0
** 0,1,1,1,0
** 0,1,0,0,1,1,1,1            ASCII code for "O" -- 0100 1111
**
** Clearly, this simple scheme can be expanded or enhanced
** any way you like.
**
** Returns -1 if any file error occurred, otherwise 0.
**/
static int read_data_file()
{
/*
** The Neural Net test requires an input data file.
** The name is specified here.
*/
const char *inpath="NNET.DAT";

FILE *infile;

int xinsize,yinsize,youtsize;
int patt, element, i, row;
int vals_read;
int val1,val2,val3,val4,val5,val6,val7,val8;

/* printf("\n Opening and retrieving data from file."); */

infile = fopen(inpath, "r");
if (infile == NULL)
{
	printf("\n CPU:NNET--error in opening file!");
	return -1 ;
}
vals_read =fscanf(infile,"%d  %d  %d",&xinsize,&yinsize,&youtsize);
if (vals_read != 3)
{
	printf("\n CPU:NNET -- Should read 3 items in line one; did read %d",vals_read);
	return -1;
}
vals_read=fscanf(infile,"%d",&numpats);
if (vals_read !=1)
{
	printf("\n CPU:NNET -- Should read 1 item in line 2; did read %d",vals_read);
	return -1;
}
if (numpats > MAXPATS)
	numpats = MAXPATS;

for (patt=0; patt<numpats; patt++)
{
	element = 0;
	for (row = 0; row<yinsize; row++)
	{
		vals_read = fscanf(infile,"%d  %d  %d  %d  %d",
			&val1, &val2, &val3, &val4, &val5);
		if (vals_read != 5)
		{
			printf ("\n CPU:NNET -- failure in reading input!");
			return -1;
		}
		element=row*xinsize;

		in_pats[patt][element] = (double) val1; element++;
		in_pats[patt][element] = (double) val2; element++;
		in_pats[patt][element] = (double) val3; element++;
		in_pats[patt][element] = (double) val4; element++;
		in_pats[patt][element] = (double) val5; element++;
	}
	for (i=0;i<IN_SIZE; i++)
	{
		if (in_pats[patt][i] >= 0.9)
			in_pats[patt][i] = 0.9;
		if (in_pats[patt][i] <= 0.1)
			in_pats[patt][i] = 0.1;
	}
	element = 0;
	vals_read = fscanf(infile,"%d  %d  %d  %d  %d  %d  %d  %d",
		&val1, &val2, &val3, &val4, &val5, &val6, &val7, &val8);

	out_pats[patt][element] = (double) val1; element++;
	out_pats[patt][element] = (double) val2; element++;
	out_pats[patt][element] = (double) val3; element++;
	out_pats[patt][element] = (double) val4; element++;
	out_pats[patt][element] = (double) val5; element++;
	out_pats[patt][element] = (double) val6; element++;
	out_pats[patt][element] = (double) val7; element++;
	out_pats[patt][element] = (double) val8; element++;
}

fclose(infile);
return(0);
}